NEWS RELEASEMonday, May 28 2012

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POSITIVE DRILLING RESULTS FROM ENDEAVOUR’S YOUGA GOLD MINE Vancouver, May 28, 2012 – Endeavour Mining Corporation (“Endeavour”) (TSX:EDV, ASX:EVR, OTCQX:EDVMF) is pleased to report positive results from drilling beneath the Main Pit at the Youga Gold Mine. Drill intercepts included A2-11-220 with 52.5 metres (m) of 2.1 grams per tonne (g/t) gold which included 2.6 m of 5.2 g/t gold.

The drilling beneath the main pit at the mine has shown a continuation of the A2 Main deposit and highlighted the potential for further pit expansion. Neil Woodyer, CEO, stated “Building on the success of our 2011 exploration campaign at Youga, we committed additional funding to accelerate our exploration and resource delineation campaign as part of our overall US$34 million exploration program for 2012. These latest drilling results demonstrate we are now reaping the benefits of this commitment to exploration.”

A series of six core holes totalling 2,636.4 m were completed and assayed in late 2011 and 2012 (Figures 1, 2 and 3) based on results of the Youga A2Main open pit design update. The expanded pit design used a higher gold price ($1200/oz) and incorporated drilling from the flanks of the A2Main and A2East deposits. The work underscored the need for additional drilling to fully test the deeper portion of A2Main deposit. Highlights are included in Table 1. Based on these positive results 10 additional holes are planned to test the mineralization at and below the ultimate pit limits. The program is a combination of reverse circulation (RC), core and deepening of existing holes and consists of a total of 3,700m of drilling. Pit mapping and structural studies have shown that the C1 and C2 faults have offset portions of the A2Main deposit and control the flattening of the mineralization on the north end (Figure 1). A wedge of mineralization between the C1 and C2 faults intersected by hole A2-11-220 will be delineated in the next round of drilling (Figure 2). Drilling in 2011 and 2012 has also demonstrated that mineralization does occur on the northeast side

For additional information, contact:

David Laing Senior Vice President – Technical Services +1 604 609 6133 dlaing@endeavourmining.com Bobby Morse James Strong Buchanan +44 20 7466 5000 bobbym@buchanan.uk.com

Florence Liberski Renmark Financial Communications +1 514 939 3989 or +1 416 644 2020 fliberski@renmarkfinancial.com

David Ikin Professional Public Relations +61 8 9388 0944 david.ikin@ppr.com.au

Endeavour Mining Corporation Cayman Corporate Centre 27 Hospital Road George Town, Grand Cayman, KY1 1109, Cayman Islands Tel: +1 345 946 7603 Fax: +1 345 946 7604 www.endeavourmining.com A Cayman Islands exempted company with limited liability. ARBN 153 067 639

EDV EVR Toronto Stock Exchange

Australian Securities Exchange

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of the C2 fault but the amount of offset is not confirmed however exploration will continue to test both sides of the fault. Table 1: A2 Main Drilling Highlights (Sorted by Northing of Intersection)

Section Hole From To Length True Width Au

Grade Final Depth Number ID (m) (m) (m) (m) (g/t) (m) 7650 N A2-11-220 207 211 4 3.4 4.3 500 and 306 367 61 52.5 2.1 including 354 357 3 2.6 5.2 including 359 364 5 4.3 4.6 7700 N A2-11-235 145 163 18 13.1 3.3 500.1 including 145 151 6 4.4 5.6 and 205 215 10 7.3 1.3 including 213 214 1 0.7 3.9 and 289 304 15 11.0 1.1 and 381 391 10 7.3 1.0 and 396 404 8 5.8 2.3 including 402 403 1 0.7 7.7 7775 N A2-11-231 51.5 55.1 3.6 2.4 3.8 534.4 including 51.5 52.5 1 0.7 6.5 including 54.2 55.1 0.9 0.6 6.7 and 72 78.9 6.9 4.6 1.7 including 74 75.5 1.5 1.0 3.3 and 367.5 376 8.5 5.7 1.2 including 374.8 376 1.2 0.8 3.3 and 454 497.2 43.2 28.9 0.8 including 477 490 13 8.7 1.3 and 505 517.8 12.8 8.6 1.2 7800 N A2-11-226 446.6 468.6 22 18.9 1.0 500.2 including 447.6 449.6 2 1.7 2.5 7850 N A2-11-236 271.6 278.6 7 5.1 3.4 361.77850 N A2-11-228 199.5 209.5 10 10 2.3 240 including 206.5 207.5 1 1 5.6

On Section 7650N hole A2-11-220 was targeted 100 m below previous intercepts of the A2Main deposit but hit mineralization shallower and further east than anticipated because the mineralization appears to have been offset (right lateral) by the C1 fault (Figure 2). Given the position of the hole relative to the C1 fault it is concluded that this may be an offset wedge of the A2Main deposit caught between the C1 and C2 faults. This opens up an area for additional mineralization but with limited strike extent. On Sections 7700N, 7775N and 7800N drill holes A2-11-235, 231, and 226 intersected the A2Main deposit at depths that are 75 to 100 m deeper than previous intercepts on these sections. Hole A2-11-231 has the deepest intercept of A2Main to date at -200 RL, which is 425m below original surface and 260 m below the final pit depth. A2-11-226 and A2-11-231 end in mineralization and may have stopped within the A2Main deposit.

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On Section 7850N, at the north end of the A2Main deposit, drill holes A2-11-236 and A2-11-228 were testing an area that had not previously been drilled. Both holes intersected the targets, with A2-11-236 returning 5.1 m (true width) at 3.4 g/t and A2-11-228 intersected 10 m at 2.3 g/t on a shallowly northeast dipping portion of the A2Main deposit. Figure 1: A2 Main Pit Drill Plan on Satellite Imagery

A2-11-220

A2-11-228

A2-11-236

A2-11-231

A2-11-235

A2-11-226

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Figure 2: A2 Main Cross Section 7650N, Looking North

Figure 3: A2 Main Cross Section 7700N, Looking North

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Qualified Persons

K. Kirk Woodman, P.Geo., General Manager Exploration is the Qualified Person overseeing Endeavour’s exploration projects in Burkina Faso, Cote d’Ivoire and Mali and has reviewed and approved this press release.

All Youga sample preparations and standard 50 gram gold fire assays were performed by SGS Laboratories, Ouagadougou, Burkina Faso. Endeavour consistently employs a rigorous quality control and assurance program comprising regular insertion of certified reference standards, blanks and duplicates.

About Endeavour Mining Corporation

Endeavour is a gold producer delivering growth. Endeavour owns two gold mines producing approximately 180,000 oz per year in Ghana and Burkina Faso that are generating significant operating cash flows to fund exploration and development growth. In addition to upside potential at its current operations, Endeavour’s gold project in Côte d’Ivoire is ready for construction (mining permit submitted; currently negotiating EPCM contract) for an additional 100,000 oz per year. Endeavour’s strong financial base encourages investments in long-term operational growth, exploration to replace and increase reserves, and funding for acquisitions.

Endeavour Mining Corporation is listed on the TSX (symbol EDV) and ASX (symbol EVR), and also trades on the OTCQX (symbol EDVMF).

On behalf of Endeavour Mining Corporation Neil Woodyer Chief Executive Officer This news release contains "forward-looking statements" including but not limited to, statements with respect to Endeavour's plans and operating performance, the estimation of mineral reserves and resources, the timing and amount of estimated future production, costs of future production, future capital expenditures, and the success of exploration activities. Generally, these forward-looking statements can be identified by the use of forward-looking terminology such as "expects", "expected", "budgeted", "forecasts" and "anticipates". Forward-looking statements, while based on management's best estimates and assumptions, are subject to risks and uncertainties that may cause actual results to be materially different from those expressed or implied by such forward-looking statements, including but not limited to: risks related to the successful integration of acquisitions; risks related to international operations; risks related to general economic conditions and credit availability, actual results of current exploration activities, unanticipated reclamation expenses; changes in project parameters as plans continue to be refined; fluctuations in prices of metals including gold; fluctuations in foreign currency exchange rates, increases in market prices of mining consumables, possible variations in ore reserves, grade or recovery rates; failure of plant, equipment or processes to operate as anticipated; accidents, labour disputes, title disputes, claims and limitations on insurance coverage and other risks of the mining industry; delays in the completion of development or construction activities, changes in national and local government regulation of mining operations, tax rules and regulations, and political and economic developments in countries in which Endeavour operates. Although Endeavour has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Please refer to Endeavour's most recent Annual Information Form filed under its profile at www.sedar.com for further information respecting the risks affecting Endeavour and its business.