Following the 11.20pm incident on Jalan Reko, the police sent the 23-year-old victim to the Kajang Hospital where he was warded.
The driver and three other passengers in the Honda Accord were detained to facilitate investigations into the attack on the victim.
Kajang police chief ACP Ahmad Dzaffir Mohd Yussof said yesterday a meat cleaver had been found in the boot of the vehicle.
He said the driver had behaved suspiciously and attempted to bribe the policemen who were examining the vehicle.
He added that initial investigations revealed the victim had gone to PV20 in Setapak to meet a man at about 10pm before he was confronted by nine others who attacked him.