BENSALEM, Pa. (AP) — Officials say a tanker truck overturned and burst into flames on a busy highway near Philadelphia, injuring two people inside and causing heavy traffic delays.

Bensalem Township police say the tanker's driver and a passenger were removed from the vehicle and taken to a hospital in critical condition.

Bensalem Public Safety Director Fred Harran tells WPVI-TV it will likely take hours to clean up the mess on a ramp onto Interstate 95 near Bensalem, about 20 miles (32 kilometers) northeast of Philadelphia.

It's not clear what caused the tanker to crash around 10:30 a.m. Thursday.

The Philadelphia Fire Department says the blaze was under control about an hour later.

Bensalem police had local schools cancel outdoor recess so children would not be exposed to the fumes from the fire.

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