LAHORE(National Times)- At least four people were killed and 19 other sustained injuries when a bus collided head-on with a trailer in Lahore on Sunday, Dunya News reported. According to details, the accident occurred at the Raiwind Road in Jia Baga area where a bus carrying wedding guests collided with a trailer, killing four persons on the spot and injuring 19 others. Police and rescue teams reached the spot and shifted the dead and injured to hospitals. According to rescue sources, 12 injured were shifted to Services Hospital while seven were moved to Indus Hospital. Rescue sources also informed that two of the injured were in critical condition. According to eye-witnesses, the accident was caused due to negligence of driver of the trailer.