FIVE RAIL CARS DERAIL NEAR SAN ANTONIO

  

Authorities say five train cars overturned outside of San Antonio, Sunday, spilling about 1,000 gallons of sodium hydroxide and prompting a temporary evacuation.

The Bexar County Sheriff's Office says the derailment happened around 4 p.m. Sunday in an industrial area southwest of the city.

Officials report the sodium hydroxide didn't cause fumes or residue, and is only dangerous if touched.

Two men inside a tug car that overturned suffered minor injuries and were treated on scene before being released.

A nearby flea market was temporarily evacuated.

KENS-TV reports the rail line involved is privately owned by oilfield services company Schlumberger.

An environment group is cleaning up, and authorities are investigating the cause of the derailment.