Mr. Joseph Conway reports

PRIMERO ANNOUNCES EXPLORATION RESULTS; ALEXA VEIN CONTINUES AND VICTORIA VEIN EXTENDS INTO WEST BLOCK

Primero Mining Corp. has released the results of recent drilling at its San Dimas mine in Mexico. Results indicate that the Victoria vein, discovered in 2012, extends into an adjacent ore block and that the Alexa vein, also discovered in 2012, continues west. These discoveries support the company's belief that this region has become a new nucleus of high-grade gold and silver mineralization capable of supporting future mining at the San Dimas mine. Results are summarized in the table.

"The confirmation that the Alexa vein continues and that the Victoria vein extends into the West block are important discoveries for the company," stated Joseph Conway, president and chief executive officer. "The Alexa and Victoria veins not only represent an important contribution to the ore expected to be mined from the Sinaloa graben over the next few years, Victoria is also one of the new veins we're opening up with long-hole mining, allowing us to significantly improve productivity at the mine. Our exploration drilling program is progressing ahead of schedule, and with continued positive results, the company may elect to expand it during the third quarter."

The Alexa and Victoria veins were discovered in the Sinaloa graben block in the first half of 2012 (1), after which the company successfully completed delineation drilling, resulting in 105,000 ounces of gold and 5.6 million ounces of silver being included in its year-end 2012 mineral reserves. As a result of its close proximity to existing infrastructure, the Victoria vein was also included in the 2013 mine plan.

The company is systematically targeting mineralization located in close proximity to existing infrastructure along the prolific central corridor. The company's planned $15-million 2013 exploration program includes 74,000 metres of diamond drilling, broken into 34,000 metres of exploration drilling and 40,000 metres of delineation drilling. In addition, the company is undertaking 3,800 metres of exploration drifting.

The 2013 drilling plan was designed to test for the extension of the Victoria vein into the adjacent West block, its extension at depth, and the extension of the Alexa vein to the west and into the adjacent Sinaloa graben block. A combined total of 33,400 metres drilling has been completed to date in 2013.

The Alexa vein was identified within two faults, the Sinaloa fault to the east and a smaller fault to the west. Surface drilling has successfully intercepted the western extension of the Alexa vein beyond the smaller western fault. Drilling approximately 125 metres south of the Alexa vein, just west of the Sinaloa fault, successfully intercepted the western extension of the Victoria vein.

The Sinaloa fault is a normal major fault that divides the Sinaloa graben from the West block. The Sinaloa fault is part of the north-northeast normal fault system that is characteristic of the San Dimas graben-horst structural framework with several minor related structures. This structural complexity produces displacements along strike and dip, offsetting the veins tens of metres in the vertical and/or horizontal direction. The Sinaloa fault, as with any normal fault at San Dimas, produces displacement along strike and dip.

Development of the Sinaloa graben tunnel, running north-south, allowed drilling access to the area where the Alexa and Victoria veins were discovered in early 2012. These veins are at a similar orientation to the prolific Roberta and Robertita vein systems, which have produced approximately 460,000 ounces of gold at an average grade of 9.1 grams per tonne, in the adjacent Central block.

The company continues exploring the upside extension of the Alexa vein into the western area and will explore for the continuation of the Alexa vein into the Sinaloa graben in the second half of 2013. The company has successfully developed access to the Alexa and Victoria veins, allowing for inclusion into the near-term mine plan and accelerated conversion to resources and/or reserves.

      SIGNIFICANT 2013 DRILL RESULTS                                     

                               Estimated
                 Grade (g/t)  true width
Drill hole         Au     Ag         (m)

VIC13_254        15.9  1,091         2.2
                 10.2    513         1.3
                 11.7    601         1.5
VIC13_255        13.2    860         5.9
VIC13_256        37.4  2,180         4.4
                100.1  6,642         1.2
                  2.1    224         0.5
                  3.4    194         0.5
VIC13_264         6.5     82         3.5
VIC13_257        16.5    606         2.4
VIC13_260         4.1    182         3.4
AL13_056          4.8    325         6.5
AL13_057         32.8  2,485         1.0
AL13_058          3.7    180         4.0
                  3.6    238         0.5

(1) Refer to the company's news releases of March 28, 2012, and June 25, 2012, available on the company's website or on SEDAR.

Technical information and qualified person/quality control notes

The scientific and technical information contained herein is based on information prepared by or under the supervision of Gabriel Voicu, PGeo, vice-president, geology and exploration, Primero, who is a qualified person for the purposes of National Instrument 43-101. Mr. Voicu has reviewed and approved the contents of this news release with respect to the scientific and technical information. Drill samples were prepared by SGS de Mexico SA de CV in Durango, Mexico.

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