By Brian Ellsworth and Vivian Sequera
CARACAS (Reuters) - Venezuelan opposition leader Juan Guaido said on Thursday intelligence agents had detained his chief of staff during a pre-dawn raid, putting to the test repeated U.S. warnings that President Nicolas Maduro should not go after his opponents.
U.S. Secretary of State Mike Pompeo, in a post on Twitter on Thursday, called for Roberto Marrero's immediate release and said "we will hold accountable those involved."
Guaido invoked the constitution in January to assume the interim presidency after declaring Maduro's 2018 re-election a fraud. He has been recognised by the United States and dozens of other Western nations as the country's legitimate leader.
Maduro, who has overseen a dramatic collapse of the OPEC nation's economy, has called Guaido a puppet of the United States and said he should "face justice," but has not explicitly ordered his arrest.
Top U.S. officials have repeatedly warned Maduro not to touch Guaido and his inner circle and threatened ever harsher sanctions intended to further isolate Maduro and cut off his administration's sources of revenue.
U.S. National Security Adviser John Bolton warned Maduro earlier this month that Guaido's safety must be guaranteed and that the world was watching.
"They have kidnapped @Robertomarrero, my chief of staff," Guaido said in a post on Twitter, adding that the Caracas residences of Marrero and opposition legislator Sergio Vergara had been raided before dawn. "We do not know their whereabouts. They should be freed immediately."
Marrero recorded a voice message as agents from the SEBIN intelligence service were trying to enter his home in Caracas' upscale Las Mercedes neighbourhood, which Guaido's press team forwarded to reporters.
"I am in my house and the SEBIN is here. Unfortunately, they have come for me. Keep in the fight, don't stop and look after the president," Marrero said.
Vergara, Marrero's neighbour, said some 40 armed SEBIN agents forced their way into their homes and spent three hours inside.
The SEBIN left with Marrero and Vergara's driver, the legislator said in a video posted on his Twitter account.
Guaido's press team also sent a video showing damage to the door of Marrero's home and its broken lock.
Guaido said that Marrero had told Vergara that agents had planted two rifles and a grenade in his house. Venezuela's Information Ministry did not immediately respond to a request for comment.
Since January, Venezuelan authorities have arrested over 1,000 people in connection with anti-government demonstrations, rights groups say.
U.N. human rights chief Michelle Bachelet said on Wednesday that Venezuelan security forces, backed by pro-government militias, have quashed peaceful protests with the excessive use of force, killings and torture.
Maduro says his government is the victim of an "economic war" led by his political adversaries and blames U.S. financial and oil sector sanctions for the country's situation.
With Washington already having imposed extensive sanctions on Caracas, the humanitarian and political costs of further blanket measures could be high, with millions of Venezuelans already suffering shortages of food and medicine.
ADVERTISEMENTVenezuela is reeling from annual inflation topping 2 million percent, which has fuelled malnutrition and preventable disease and spurred an exodus of more than 3 million citizens in since 2015.
While President Donald Trump has said all options remain open, there appears to be little support in Washington or regional Latin American capitals for any military intervention.
"The United States condemns raids by Maduro's security services and detention of Roberto Marrero," Pompeo said on Twitter, noting those responsible would be held to account.
Guaido had travelled around South America in February to drum up diplomatic support for his government, defying a travel ban imposed by the pro-government Supreme Court.
He later entered the country via Venezuela's principal airport without being detained by immigration officials.
ADVERTISEMENTVenezuela's chief state prosecutor, Tarek Saab, last week asked the Supreme Court to open an investigation into Guaido for alleged involvement in the "sabotage" of the country's electrical network, after the longest nationwide power blackout in decades.
The opposition, along with electrical experts, said the power outage was due to the government's incompetence and years of little maintenance.
(Reporting by Brian Ellsworth and Vivian Sequera; Additional reporting by Corina Pons; Writing by Angus Berwick; Editing by Daniel Flynn and Bernadette Baum)