Security forces foiled apparent attempts to bomb the US Embassy and an American base in Afghanistan ahead of an international donors meeting Tuesday in London to discuss the country's future. Authorities have said they fear that militants opposed to Afghanistan's U.S.-backed government may time high-profile attacks to coincide with the two-day meeting. Security forces on Monday defused two roadside bombs found in a ditch about 300 meters from the US Embassy in the capital, Kabul, said Ehbrar Ahmad, a senior official with a police commando squad. The bombs were found on a road leading from Kabul's airport to the embassy, which is surrounded by rows of bomb barriers and is tightly guarded. The road is frequently used by embassy personnel and foreign security forces.