Two people were fatally shot in less than 10 minutes and the entire police radio system crashed citywide when Commissioner Charles H. Ramsey called for help at the scene of a domestic dispute.

The infamous $62 million Motorola radio system - including its backup system - was down for more than 40 minutes, forcing cops to retreat to their headquarters and pair up in patrol cars while crimes were still being committed on the street, officials said.

It all started at 7:15 p.m., when an unidentified man in his late 20s to early 30s was found shot to death inside a parked car on Green Street near 13th, in North Philadelphia, police said.

The motive for the shooting remained unclear, and no arrests were made.

At 7:24 p.m., another unidentified man in his 20s was shot across the street from his rowhouse on the corner of 20th and Boston streets, in North Philadelphia.

The victim, who police say was the intended target, was sitting on a wooden chair when a gunman pulled up, fired several shots and drove off. The victim was pronounced dead shortly before 8 p.m. at Temple University Hospital.

Ramsey, who was at a community meeting in South Philadelphia when the shootings occurred, told a Daily News reporter afterwards that he intended to visit both crime scenes.

Ramsey huddled with homicide detectives at 13th and Green for a while and then set off to visit 20th and Boston streets.

But along the way Ramsey said he stopped to break up a drunken scuffle that was unfolding about 9 p.m. across the street from Edgar's Place, a bar on the corner of Cleveland and Cumberland streets.

Two men were trading blows after one accused the other of touching his girlfriend inappropriately. Their wild behavior prompted Ramsey to issue an assist officer call, which drew dozens of cops from across the city to the scene. The two men were taken into custody.

"We were just driving down the street and came upon it," said Ramsey, who appeared unaffected by the heightened commotion swirling around his vehicle. "There are a lot of officers who do a hell of a lot more than I do," he said.

But the dramatic response also caused the police radio system to crash, leaving cops stunned as their cars were suddenly enveloped in silence, officals said. Police officials said that the system was back on line by about 10:30 p.m.

The system had briefly crashed on Monday when lightning struck a communications tower, said FOP president John McNesby.

The Motorola system has been maligned since the city started using it in 2002. In April, the Daily News found that the system was still plagued with problems and had failed 14 times since the city and Motorola claimed to have fixed it in 2005.

"This was a crisis tonight," McNesby said. "Once again, we see the radio system doesn't work - from the rookie on the street up to the commissioner." *