(Reuters) - More than a dozen Afghan soldiers suspected of plotting to attack the Defence Ministry in Kabul were arrested after 10 suicide vests were found inside the ministry, the New York Times reported, citing Afghan and Western officials.
Security across Afghanistan has worsened after a string of incidents that have enraged Afghans in recent weeks, including the shooting deaths of 17 civilians in the volatile south more than two weeks ago blamed on a U.S. sergeant.
The New York Times reported that the Defence Ministry went into "near-total lockdown" on Tuesday after the vests, which have pouches which suicide bombers pack with explosives for use in attacks, were found inside the ministry.
The building is in one of the most heavily fortified areas of the Afghan capital and is less than a mile from the presidential palace and the headquarters of the NATO-led foreign force in Afghanistan.
The news paper said possible targets included commuter buses for government employees as well as the ministry.
The arrest of the Afghan soldiers over the suspected ministry plot is particularly worrying following a spike in attacks by Afghan forces on NATO troops in recent weeks.
Another three foreign troops, including two Britons, were killed in attacks by Afghan security forces personnel on Monday.
The increase in "insider" attacks follows the shooting massacre in Kandahar, the inadvertent burning of copies of the Koran by U.S. soldiers at the main NATO base and a video of U.S. Marines urinating on the bodies of Afghan Taliban fighters.
The attacks on foreign troops by Afghan security personnel have raised doubts about the ability of Afghan forces to take over security responsibilities under a timeline that will see the last foreign combat troops leave by the end of 2014.
The New York Times said the Defence Ministry plot was uncovered on Monday. While it said the ministry declined to confirm the incident, it said at least half a dozen unidentified Western and Afghan officials had confirmed the plot.
The BBC also reported that up to 11 vests had been found and that up to 18 people had been arrested.
The New York Times said the vests were mainly found in guard sheds around a ministry parking lot.
"You have to be cautious when you come here. It is not safe here," it quoted one unidentified Afghan army officer as saying. The officer also said the plotters "have links inside the ministry. Otherwise, they could not enter such a highly secured place".
The BBC quoted Defence Ministry spokesman Dawlat Wazeri as saying reports of the plot were just "rumors".
Security was tightened in the main diplomatic enclave of Kabul after the plot was unearthed, the New York Times said.
Last September, insurgents holed up in a partially constructed building in the same area showered the U.S. embassy and NATO headquarters with rocket-propelled grenades and gunfire in an attack lasting more than 20 hours.
(Reporting by Paul Tait; Editing by Robert Birsel)