Another rocket fell late Monday outside an Afghanistan base where South Korean aid workers and troops are stationed, but there were no injuries, Foreign Ministry officials said Tuesday.

There have now been four attacks in May alone, with the latest apparently targeting the base in Charikar City in the northern Afghan province of Parwan. A total of nine attacks have occurred so far this year near or inside the base since the first shelling on Jan. 20.

“One rocket fell south of the base in Charikar at around 11:27 p.m. Monday local time. There were no injuries and damages to our facilities there,” a ministry official told reporters, declining to be named.

“The rocket came not from a (nearby) town, but from behind the base. We will investigate the incident in cooperation with the local Afghan police.”

The attack came as public worries have deepened over the possibility of international terrorism against people of the key U.S. ally in Asia since U.S. Navy commandos shot dead al-Qaida leader Osama bin Laden on May 1.

Some experts have pointed out that international terrorist groups could target South Korea given its six-decade alliance with the U.S., which has spearheaded the war on terrorism since the massive terror attack on its soil on Sept. 11, 2001.

Seoul officials speculate that the series of attacks against the South Korean base could be launched by the militant Taliban forces in reprisal for the death of the al-Qaida leader.

Since April, the South Korean military contingent, “Ashena” unit, has beefed up its vigilance following tips that terrorist networks have stepped up their offensive against its forces.

Pointing out such deteriorating security conditions there, some people here have begun calling for an early pullout of South Koreans from the country.

By law, South Korean troops and aid workers, who were dispatched to Afghanistan last July, are to operate until December next year. Without parliamentary approval for the extension of the service period, they should withdraw by that time.

More than 300 South Korean troops have been deployed to Charikar City to protect the Korean civilians working there as part of the Provincial Reconstruction Team to help rebuild the war-torn country.

About 90 South Korean aid workers and police officers are operating in the PRT there. In Afghanistan, some 15 countries are participating in the PRT operation under the protection of the NATO-led International Security Assistance Force, which consists of troops from 46 countries.

The primary task of the PRT is to help bolster the administrative capabilities of the Afghan provincial government and stabilize the region. It also offers medical services, assistance for agricultural development, and vocational and police training.

By Song Sang-ho (sshluck@heraldcorp.com)