The Venezuelan President, Hugo Chavez, has said that powerful international forces are behind the presence of a group of alleged Colombian paramilitaries near the capital, Caracas.
By James Menendez
BBC correspondent in Caracas
President Chavez said more than 100 men had now been arrested following the discovery of their camp on Sunday.
Ties between Chavez and the US are very strained
Speaking on national television, Mr Chavez called the presence of alleged Colombian paramilitaries an invasion of Venezuelan territory - an invasion, he said, planned and directed from abroad, in particular from the United States and Colombia.
But, he added, powerful groups inside the country were also responsible, and he blamed elements within Venezuela's opposition for conspiring to overthrow him.
The government has already issued warrants for the arrest of 10 serving and retired military officers and it has carried out at least two dozen searches of properties belonging to politicians and some wealthy businessmen.
But the coalition of opposition parties, the Democratic Co-Ordinator, denies any involvement in the alleged plot, saying the government has failed to come with any credible evidence.
And there have been similar denials by both the United States and Colombia.
The US ambassador to Venezuela again publicly rejected the charge that Washington knew of a plan to overthrow President Chavez.
He also said that Venezuela had asked the US to remove its liaison officers from military bases around the country - a sign, if one were needed of just how strained relations have become.