HERAT, Afghanistan (Reuters) - Taliban insurgents led by suicide bombers attacked an Italian military base and set off another explosion in western Afghanistan on Monday, killing four people and wounding dozens, officials said.
The Italian-run base was the main target of the assault, which lasted several hours, Afghan and Italian officials said, but the Taliban said a second bomb intended for the NATO facility had gone off prematurely in the center of Herat.
The attacks were especially worrying for foreign forces because normally-peaceful Herat, near the border with Iran, is one of seven areas where they will begin handing over security to Afghans in July.
That handover is part of a process that will lead to all foreign combat troops leaving Afghanistan by the end of 2014. Some U.S. lawmakers and analysts have questioned the wisdom of the timetable with violence still at such high levels.
Dawood Saba, the governor of Herat province, said a suicide bomber in a small truck blew himself up at the entrance of the Italian-run NATO base.
Three insurgents took cover in a building near the base after the initial explosion and gunfire and intermittent explosions rang out over the city for several hours.
Mohammad Zia Mahmoudi, deputy police chief for western Afghanistan, said the last three insurgents were killed when part of the building they were fighting from was destroyed.
Taliban spokesman Qari Yousuf Ahmadi told Reuters by telephone from an undisclosed location, that four bombers had launched the attacks.
He said the vehicle bomb that exploded in the center of the city had also been meant to attack the Italian base but Afghan troops had intercepted it and the bomb went off early.
Many of the casualties appeared to have been caused by the second bomb, Afghan officials said. Ghulam Farooq, a senior Herat police official, put the number of wounded at 37, most of them civilians.
In Rome, Italian Defense Minister Ignazio La Russa said five Italian soldiers had been wounded, one seriously. He said small-arms fire into the base followed the initial blast.
"From the roofs of nearby houses they fired into the compound," La Russa told reporters.
Reuters pictures taken at the base showed one Italian soldier bleeding from a head wound next to the rubble of a partially destroyed wall.
Pictures taken outside the Italian-run base, which houses a joint civilian and military provincial reconstruction team, showed extensive damage, with parts of the wall, gate and a guardhouse destroyed.
Several vehicles were flipped over by the force of the blast, which shattered windows for some distance and left rows of burned bicycles and cars outside the base.
Violence has spiked across Afghanistan since the Taliban announced a spring offensive at the beginning of May.
The Afghan government and security forces and foreign military targets have been singled out in increasingly deadly assaults in cities across the country as militants attempt to show they retain the capacity to launch major strikes.
On Saturday, the powerful chief of police for all of northern Afghanistan was among seven people killed in an attack in the main city of Takhar province.
Initial reports said that blast had been carried out by a suicide bomber dressed as an Afghan policeman but Afghanistan's intelligence agency, the National Directorate for Security (NDS), said on Monday that may not have been the case.
The NDS said in a statement subsequent investigations suggested explosives had been hidden in a corridor outside the Takhar governor's office and were detonated remotely.
U.S. commanders had warned of a potential surge in violence as insurgents attempted to hit back after U.S.-led ISAF troops and Afghan forces made major gains in operations in the Taliban heartland in the south over the past 12 months.
Italy has about 3,880 troops serving in Afghanistan, the majority of them in the west, making it the fifth-largest contributor to the NATO force.