It happened around 2:30 a.m. on Thursday on Broad Street in the city's Spring Garden section.
The bus driver pulled up in front of Philadelphia Police headquarters to get help. Luckily, there was a 9th district officer outside the police station when the bus stopped and a passenger was able to run out and tell the officer what was happening.
Police say a 45-year-old man attacked a 61-year-old man with the cleaver in the back of the bus.
When the officer approached the bus, he saw two men covered in blood and holding each other. One of the men was said to be wielding a meat cleaver.
The officer told the man to drop the knife, which he did.
It was eventually learned that the person who the officer told to drop the weapon was actually the victim who had taken it away from his attacker.
"According to individuals on the bus, the individual with the meat cleaver started chanting -- saying some things, possibly had some mental health issues," said Chief Inspector Scott Small with the Philadelphia Police Department.
The victim has wounds to his head and hand. The attacker also had a small cut to his hand, however, police said they aren't sure how that happened.
"We're really fortunate because the victim was struck in the head with a meat cleaver, which could actually be deadly," Small said.
Both were taken to nearby hospitals.
Police say the two men don't know each other.
There were eight people on the bus at the time, so police said they have multiple witness accounts. Police also said they should have interior surveillance video from inside the bus.
The suspect was taken into custody and the meat cleaver was recovered by police.
Police say the man will possibly be charged with aggravated assault and possessing an instrument of crime and other offenses.
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