A crash between five cars and a truck on the Hume Highway south of Campbelltown has left one person dead and caused peak-hour traffic queues of up to 10 kilometres, after police were forced to close the road in both directions.
All southbound and northbound lanes on the Hume Highway have since reopened.
A person travelling in the truck was killed and 14 people, including a one-month-old baby and two toddlers, were taken to hospital after the crash near Narellan Road about 2.15pm on Tuesday.
A 55-year-old woman was flown to Westmead Hospital in a serious condition.
A one-month-old baby and two children with minor injuries were among 11 other people taken to Liverpool and Campbelltown hospitals after the crash.
At one point on Tuesday afternoon, traffic heading north was backed up over 10 kilometres to Brooks Road at Ingleburn, a spokeswoman from the Transport Management Centre said, while southbound traffic stretched back five kilometres to Menangle Road.
Drivers heading south were diverted on to Campbelltown Road.
About an hour earlier, a man was left trapped in his car after a crash on nearby Cambridge Road in Glenfield. The man, believed to be in his 60s, suffered serious head and neck injuries in the two-car crash and was flown to Westmead Hospital.
A woman in the other car, believed to be in her 40s, was taken to Liverpool Hospital with less serious injuries.
smh.com.au, with Alexandra Back