The arrested younger brother of the Manchester suicide bomber knew of his attack plans and was plotting terror in Tripoli, according to Libyan security officials.

Hashem Abedi was arrested in the Libyan capital having travelled to the city from the UK on April 16, Libya's counter-terrorism force said.

Issuing a photo of the arrested suspect, an official said he was "aware of all the details" of Salman Abedi's deadly attack on Manchester Arena and was planning his own "terrorist act" in Tripoli.

ITV News Security Editor Rohit Kachroo earlier said he had been held by counter-terrorism police on suspicion of links to so-called Islamic State.

Hashem Abedi's arrest - a day after older brother Ismail was held - came as the men's father was also arrested in the Libyan capital.

Eight people have been held in the UK and Libya since Monday's blast, which claimed 22 lives and injured dozens of people.

ITV News Middle East News Editor Lutfi Abu Aun said witnesses saw father Ramadan Abedi being taken away by masked gunmen, who arrived in two cars, while he recorded a TV interview.

Mr Abedi earlier claimed his son is innocent, telling The Associated Press by telephone from Tripoli: "We don't believe in killing innocents. This is not us."

Three other people were held in South Manchester in relation to the attack, while a woman was arrested after an armed raid on a block of flats in the north of the city.

Another man was arrested in Wigan having been tackled to the ground by armed police after he was seen with a suspicious package.

Elsewhere, a woman was arrested in an armed raid at a block of flats in north Manchester, before a man was detained in Nuneaton, Warwickshire.