Nine vehicles piled up on the New Jersey Turnpike on Wednesday. Seven tractor trailers and two cars were involved in the pileup, which occurred around 2 p.m. Sources said the highway accident occurred in an area having three lanes in each direction. While there were no serious injuries, the pileup caused a 13 mile backup on the Turnpike stretching through Mercer and Middlesex counties, as far as East Brunswick. Sources said the accident caused delays even on the northbound Turnpike when "rubberneckers" slowed down to have a gander at the crash. One truck was heavily damaged from the accident, and wasn't cleared from the roadway until almost three hours after the pileup. The area in which the accident occurred is set to eventually have six lanes going in each direction. The expansion is part of an ongoing program to widen the roadway between Turnpike Interchange 6 in Mansfield Township, Burlington County, and Interchange 9 in East Brunswick. Sources didn't indicate the cause of the accident, which is presumably still under investigation. When multiple cars are involved in an accident, though, it is sometimes more difficult to pin down what the exact cause was or who is at fault and to what extent. It is somewhat surprising, and fortunate, that nobody was seriously injured or killed in the accident. Large trucks can, of course, be very destructive in an accident. The fact that seven large trucks were involved in the accident is interesting, though, and probably indicates that there were a number of tractor trailers in relatively close proximity and also highlights the difficulty large trucks have in avoiding a crash in tight traffic conditions. Source: Star-Ledger, "Nine-vehicle accident causes 13-mile traffic backup on N.J. Turnpike in Central Jersey," Mike Frassinelli, 4 May 2011.