It was a miserable morning for commuters on the Maryland side of the Capital Beltway. Three major accidents tied up traffic for hours, but state police said the roadway was open again before the evening rush hour.

The first accident occurred shortly before 5 a.m. on the outer loop of the road just before the exit to Interstate 270 in Montgomery County when a tractor trailer laden with lumber overturned on top of a passenger vehicle. Police and fire officials said one person was killed and at least two others injured.

The outer loop was shut immediately as rescue workers struggled to extricate people from the wreckage. By 6 a.m., police had reopened the shoulder and had two other lanes open at 9:30 a.m. But much of the traffic was still being diverted to side roads.

Those detours created slowdowns for westbound traffic, which had backed up several miles during the morning rush hour. Interstate 270 northbound, Old Georgetown Road northbound and Randolph Road westbound were also slowed as motorists attempted to detour from the accident scene.

Maryland State Police opened all lanes of traffic on the outer loop of the Capital Beltway near Interstate 270 around 2 p.m., said Capt. Suzanne Jordan, commander of the state police Rockville barracks. Police opened two of the highway's four lanes by about 9:30 this morning, Jordan said.

The second accident, which was reported about 9 a.m., involved two passenger vehicles on the inner loop of the Beltway near the intersection with Branch Avenue. All traffic on the Beltway was closed only while police brought in an emergency medical helicopter to take one of the people involved to a hospital.

A third accident at about 10:15 a.m. on the outer loop of the Beltway near New Hampshire Avenue involved four cars. State police closed both the inner and outer loops of the road to allow a helicopter to land to transport the injured to area trauma centers. The roadway was reopened fully by 12:30 p.m. today, said Maryland State Police Sgt. Ernie Ford.

Capt. Chauncey Bowers, Prince George's County fire spokesman, said the accident involved four vehicles: a box truck, two cars and a pickup truck. Three passengers -- two in one car, one in the other -- had to be cut out of the vehicles and were flown to hospitals. Their conditions appear to be non-life-threatening, Bowers said.