A group of 16 Americans were jailed Thursday after staging demonstrations at the U.S. Embassy and a U.S. air base and will probably be expelled from the country, a police official said.

Maj. Manuel Urbina, spokesman for the Public Security Forces, said the Americans were protesting Reagan administration policy in Central America when they were arrested in front of the embassy and the U.S. air base in Palmerola, about 40 miles northwest of the capital.He said four of the protesters were being held at the Casamata prison in Tegucigalpa and the other 12 at a police jail in Comayagua, four mile away.

In a similar protest in Guatemala City on Wednesday, four Americans threw blood on the steps of the U.S. Embassy, chained themselves to the gates of the compound and demanded an audience with the U.S. ambassador, James Michel.

No arrests were reported.

The demonstrations were organized by a group called Project Independence and held one day before Thursday's celebration of the anniversary of Central America's independence from Spain in 1821.