International peacekeepers in Afghanistan have seized a large cache of rockets in a joint operation with Afghan forces.
Some 150 Chinese-made 107 mm rockets were found on the road north of the capital, Kabul, to the Bagram air base.
The rockets are thought to be of the same type as those fired at the international peacekeeping force (Isaf) earlier in the week.
Earlier, the UN said that one its workers had been murdered in the north of the country, adding to fears about the security situation in Afghanistan.
Arrests
An Isaf spokesman, Lieutenant Joel Fall, described the rocket find as "quite significant."
However, it was not immediately clear who they might have belonged to.
Two rockets were fired at an Isaf compound in the capital on Sunday, although no injuries were suffered.
Reuters quoted Interior Ministry security chief General Mohammad Joorat as saying that several people had been arrested in connection with that incident.
He also said there had been more arrests of people suspected of involvement in a plot against the interim government.
The plot was revealed last week, when the Kabul authorities said they had rounded several hundred suspects in the capital suspected of planning attacks against the government.
The detainees were linked to the Hezb-e-Islamic faction, a group headed by former mujahideen commander Gulbuddin Hekmatyar.
Earlier this week, Afghanistan's interim Defence Minister Mohammad Fahim survived an apparent assassination attempt while visiting the east of the country.
UN death
The UN said that Shah Sayed of the UN Food and Agricultural Organisation was shot dead on Wednesday in his home in the city of Mazar-e-Sharif.
UN spokesman Manoel de Almeida e Silva said three people entered Mr Sayed's house and took him outside and shot him dead.
The motive for the killing is as yet unknown, but it did not look like a robbery, he said.
Reports said the UN will complain to Afghan authorities about the growing number of attacks on aid workers in the north of the country.
Mr Silva said the UN's special representative for Afghanistan, Lakhdar Brahimi, would meet top security officials to seek better protection for humanitarian workers.
He said that in January, three people were beaten as they handed out aid and in February, armed men entered the home of an Afghan aid worker, raped women and looted the house.
Fears are growing in Afghanistan that the security situation is deteriorating as crime and local rivalries emerge in the wake of the war against al-Qaeda and the Taleban.
