New Orleans — Slippery roads led to a car and a tour bus collision in eastern New Orleans on Thursday morning that killed the car’s driver and forced the closure of Interstate 10.

New Orleans police said an unidentified woman’s car hydroplaned while traveling eastbound on I-10 near Michoud Boulevard shortly before 11:22 a.m., according to Officer Hilal Williams, a police spokeswoman. Williams said it’s unclear what caused the woman to hydroplane or how fast she was driving, but she lost control of her vehicle and crossed into oncoming traffic.

Her maroon Honda Accord was struck in the rear by a charter bus carrying elementary school children and their parents from Florida, Williams said. The impact crumpled the small car and tossed it from the roadway while the bus swerved into shrubbery on the side of the roadway, she said.

The victim, whose identity and age have not been released, died at the scene. Williams said four of the more than 40 people on the bus were injured, though none seriously, and they were treated at a local hospital.

The accident shut down the interstate for more than two hours, and forced drivers to take alternate routes to and from St. Tammany Parish. Williams said the cause of the crash still remains under investigation.

Kingdom Coach of Alabama was the operator of the bus involved in the crash. The company, which has been in operation since 2002, said the vehicle was part of a caravan of three buses bringing students from Crestview, Fla. to New Orleans for a field trip.

The company said it is cooperating with police and other authorities to determine the cause of the accident.

Thursday’s accident was the second time the interstate has been closed because of fatal crash in the past two months. In March, police investigated a hit-and-run accident that left a motorcyclist dead near the I-10 highrise.

In that incident, authorities said the cyclist was speeding and struck a tractor trailer, which never stopped after the accident. The accident shut down the bridge for some time. Police never located the driver in that incident.