DALLAS (AP) _ A tractor-trailer containing 2 tons of military explosives overturned today along an interstate highway, injuring the driver.

Army explosives experts were sent to determine how to remove the missile components safely.

''I don't know yet if we are looking at the threat of an explosion or a fire or having to detonate or dispose of the ordnance,'' said Liz Crossan, a spokeswoman at Fort Hood.

Fire investigators said the driver was reaching for coffee about 3:30 a.m. when he lost control of the rig on Interstate 20. The truck smashed through the median and came to rest off under elevated lanes of I-35.

The explosives remained inside the rig's twin trailers.

The wreck blocked rush-hour traffic on I-35 and I-20 for hours. Ramps at the interchange remained closed.

''We don't want people driving on elevated lanes over the top of this,'' Fire Department spokesman Carolyn Garcia said.

The unidentified driver suffered minor injuries, authorities said.

A private hauler was taking the cargo from El Paso to Atlanta, Ms. Garcia said.