All 22 crew members of a ship that was subject to a “suspected hijacking” in the English Channel have been confirmed safe, health secretary Matt Hancock has said.

Seven men have been arrested on suspicion of seizing or exercising control of a ship by use of threat or force. They all remain in custody at police stations across Hampshire.

What happened on board?

It is understood that the 228-metre tanker was carrying 42,000 tonnes of crude oil and had been expected to dock in Southampton at 10.30am on Sunday.

Hampshire Police said they were alerted to concerns over the welfare of the crew as the ship was six miles off the coast of Bembridge, having set sail from Lagos, Nigeria.

The vessel is registered in Liberia and operated by Greek shipping firm Folegrandos.

“It was reported that a number of stowaways were on board, and they had made threats towards the crew,” police said.

What was the response?

Armed forces personnel were authorised by home secretary Priti Patel and defence secretary Ben Wallace to board the Nave Andromeda off the Isle of Wight after a tense 10-hour stand-off.

Speaking to Sky News on Monday morning, Hancock said: “I can confirm that the crew are safe and the operation to secure the vessel has concluded successfully.”

The raid was likely to have been carried out by members of the Special Boat Service (SBS), the elite maritime counter-terrorism unit of the Royal Navy. SBS operations are highly classified and not officially confirmed.

According to the MoD, its personnel mostly consist of Royal Marine Commandos who “specialise in daring undercover raids that exploit the element of surprise”.

In a statement, the Ministry of Defence said Armed Forces personnel boarded the ship to “safeguard life and secure a ship that was subject to suspected hijacking”.

“Armed forces have gained control of the ship and seven individuals have been detained,” a spokesperson said.

“Police investigations will now continue. Initial reports confirm the crew are safe and well.”

Four military helicopters – thought to have included two Merlin Mk 4s, a Wildcat and a Chinook – took 40 personnel to the ship, The Times reported.

The paper quoted a defence source as saying about 16 SBS members went aboard the tanker backed by airborne snipers and secured it in nine minutes.

What has been said about it?

Tobias Ellwood, chair of the Commons Defence Committee, said the boarding of the tanker was a “good outcome”.

He told BBC News: “Seven stowaways on board taking over a ship or causing the ship not to be in full command would have triggered a multi-agency alarm and then well-rehearsed classified protocols were then put into action.”

Defence secretary Wallace commended “the hard work of the Armed Forces and police to protect lives and secure the ship”.

“In dark skies, and worsening weather, we should all be grateful for our brave personnel,” he said. “People are safe tonight thanks to their efforts.”

In a tweet, Priti Patel said she was “thankful for the quick and decisive action of our police and armed forces who were able to bring this situation under control, guaranteeing the safety of all those on board”.

Hampshire Police said: “Following a multi-agency response by police with support from the military and other emergency service partners, seven people were detained by police.”

They also confirmed all crew members were safe and well.