UPDATE: Shortly after 4:30 p.m., Virginia State Police announced that both lanes on Interstate 81 had been reopened.

AUGUSTA COUNTY, Va. (WRIC) — A tractor-trailer crash on northbound I-81 has caused a hazmat incident with cleanup underway near Greenville, Virginia. The interstate will remain closed for the next several hours, VDOT says.

Hazardous materials were spilled, according to the Virginia Department of Transportation (VDOT). The incident happened around 4 a.m. Tuesday and both northbound lanes will remain closed until hazmat cleanup is complete.

The truck’s cargo included a flammable powder that must be removed before northbound I-81 can reopen, according to VDOT.

Northbound I-81 traffic is being detoured at the Fairfield exit in Rockbridge County.

VDOT is warning drivers of major delays in southern Augusta County and northern Rockbridge County on northbound I-81 and Route 11.

For updated traffic alerts and travel information, dial 511 or go to http://www.511Virginia.org.