Police in Venezuela say they have arrested a leader of the strike which failed to oust President Hugo Chavez two years ago.
Costa Rica withdrew Carlos Ortega's asylum last year
A police official said Carlos Ortega was captured in the capital Caracas and that he was carrying identity papers with an assumed name.
The trade union leader is accused of treason and of fomenting rebellion.
Mr Ortega played a key part in the two-month strike which paralysed Venezuela's vital oil industry.
Family members say he secretly returned to Venezuela last August, after fleeing to Costa Rica two years ago.
"This person is being held by prosecutors," national police director Marcos Chavez told state television.
"The citizen Carlos Ortega faces charges of civil rebellion and treason against the nation."
As leader of the Venezuelan Labour Federation, Mr Ortega was a principal organiser of the strike in Venezuela which began in late 2002 when protesters demanded Mr Chavez's resignation.
The action severely dented the output of Venezuela's primary export, oil, and in some areas caused food and fuel shortages.
Chavez: Briefly ousted in a 2002 coup
Mr Chavez was briefly ousted from power during a short-lived coup in 2002.
The president won a referendum on his rule in August 2004, and followed it with regional election victories that strengthened his grip on power.
Correspondents say the country remains deeply polarised.