ABERDEEN, Md. (WJZ/AP)— State police continue to investigate a bus accident on I-95 that sent a dozen people to the hospital and caused major traffic backups Friday morning.

Twelve people suffered non-life threatening injuries in the accident after a charter bus ran off the road and hit a guardrail on I-95 in Aberdeen.

The accident was reported about 9 a.m. near Route 22. Emergency officials say the bus was carrying 48 passengers. The bus was carrying a group of teachers from Newark, Del., to an outing at the Inner Harbor in Baltimore.

Maryland State Police said some passengers complained of minor injuries. The cause of the accident is under investigation.

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