On Friday, two teenage brothers, 14 and 15, and their cousin, 19, were shot and killed in the Cuautepec area, El Universal reported.
Police said the three victims were killed during a dispute over drug sales. Investigators found bags of cocaine and marijuana on the bodies.
"We know that drug dealing is an issue of which drug was in place and obviously we will strengthen the area with important actions," said Public Security Secretary Jesus Rodriguez Almeida.
On Thursday, gunmen entered a mechanic's workshop and shot at a mechanic and a customer, the news report said. One of the men died at the scene, while one died later at a hospital. Police said the shooting was likely over drug sales.
Meanwhile, Francisco Rafael Arellano Felix, a former member of Mexico's Tijuana Cartel was shot and killed at a tourist area in Cabo on Friday, CNN reported.
Authorities said the attack was carried out by two men wearing clown costumes.
Arellano Felix, 63, served time in prisons in Mexico and the United States for drug and weapons charges, the Los Angeles Times reported.
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