Fresno police have increased the reward for tips leading to arrests in two separate murder investigations to $3,000. The first killing occurred on March 15 at an apartment complex in which a roommate disturbance led to the death of 32-year-old Shannon Ivory. In the second case, Michael Dorsey, 40, is suspected of killing 38-year old Perry Paul Espinosa after a fight. Both men are believed to still be in Fresno. The firearms used in both murders have not been located.