Taliban insurgents have captured a strategic district in embattled Helmand Province, according to officials, while Afghan troops were evacuated from the area and Air Force planes bombed military installations there to prevent the Taliban from using them.

The district of Sangin was once a prize over which insurgents battled British and American troops for control, with high casualties on all sides. For the past year, Taliban forces have been pressing to retake it as part of their broader push to dominate the desert province bordering Pakistan.

Officials said there was heavy fighting in the area overnight and that Afghan troops were moved to a military base about a mile away, according to government officials cited in Afghan TV news reports. After they reached safety and withdrew their equipment, their installations were bombed and destroyed. There were no immediate details on casualties.

An army spokesman in the region, reached by phone, however, said there had been no serious fighting and no casualties. He said local security leaders had decided to evacuate their forces yesterday afternoon after learning that Taliban fighters had entered the homes of local residents.

“We didn't want to fire back to avoid civilian casualties,” said Mohammed Rassool. “The military council decided to order a retreat.” However, he added that the Taliban have been “trying for years to capture Sangin. They did it yesterday.”

The Taliban already controls several large districts in Helmand, and its forces have surrounded and attempted to attack the capital city, Lashkar Gah, for months. American forces were sent there late last year to help beat back the insurgents.

Less than two months ago, the Taliban launched a heavy attack against government positions in Sangin, killing more than 100 soldiers and police, but they were driven back with help from extra troops and air strikes. Officials said they used tunnels from private houses to reach front-line government checkpoints.

Sangin is a town of 30,000 in the heart of Helmand's opium producing region. After the Taliban regime was ousted in Kabul in 2001, Sangin remained under Taliban control, in alliance with local tribes and drug traffickers, for several years before British forces arrived and set up a base there in the summer of 2006.

For the next nine months, Taliban forces besieged the Western troops in one of the longest and fiercest clashes of the war. Nato officials compared the combat to the Korean War, and British soldiers nicknamed the area “Sangingrad,” after the battle of Stalingrad in World War II.

In April of 2007, more than 1,000 international troops assaulted the area and occupied it after most Taliban fighters had left, and Sangin was restored to government control.