A Vietnamese man suspected of being a high-ranking member of a people-smuggling network has been arrested in Birmingham, police said.
He was detained as a building in Handsworth was raided early on Monday.
The National Crime Agency (NCA) said the man, 23, was held after he tried to get out of a window on to a flat roof.
Police added the arrest was part of an investigation into the smuggling of mainly Vietnamese migrants into the UK in the backs of lorries in 2020.
Officers also seized cash, estimated to be about £10,000, from the property.
The man is being questioned on suspicion of assisting illegal immigration to the UK and money laundering offences.
Paul Boniface, from the NCA, said: "We are determined to disrupt and dismantle people smuggling networks wherever they are operating."