The deaths on Tuesday came despite a military crackdown against violent drug gangs in the surrounding area of Guerrero state.
As other men filmed the attacks, the group opened fire with assault rifles at one station, killing three policemen.
The attacks took place about 15 km north of the tourist zone in the neighbourhoods of Emiliano Zapata and Ciudad del Renaciemento and left five state police investigators and two secretaries dead.
Enrique Gil Mercado, a special prosecutor for the attorney general's office in Guerrero state said about eight gunmen took part in each attack and all escaped.
He said he did not immediately know how many people were injured. Officials also did not provide a motive for the attacks or comment on why the assailants videotaped the killings.
Franck Contreras, a Mexican journalist, told Al Jazeera the killings demonstrated the level of violence the drug cartels could unleash against the police despite the immense security deployment in the region by the government.
Felipe Calderon, the Mexican president, called an emergency meeting with his security cabinet to discuss the attacks.
Since taking office on December 1, Calderon has made tackling Mexico's organised drug gangs one of his top priorities, sending troops to violent regions such as his home state of Michoacan.
Two thousand people were killed in drug related feuds last year alone.
In January 8,000 troops and federal police were sent to Guerrero state around Acapulco.
As part of the clampdown, soldiers have been investigating local police forces for connections with the drug cartels. In the border city of Tijuana, just south of San Diego, the army confiscated all the city police's guns.
As part of the clampdown, soldiers have been investigating local police forces for connections with the drug cartels. In the rowdy border city of Tijuana, just south of San Diego, the army confiscated all the city police's guns.
But despite the crackdown, there were 190 drug gang-related deaths in Mexico in January, just a handful less than a year ago.
There are fears gangs could now be striking back by targeting security officials.
Acapulco, a once glamorous tourist destination now popular with US students during "spring break", has been hit by a brutal war between rival gangs that have staged shootouts in broad daylight near tourist areas as they fight for strategic smuggling routes for transporting cocaine into the US.
In the latest grisly killing police said on Sunday that a man's chopped-up body was discovered in the town dumped in plastic rubbish bags.