UK authorities have arrested another suspect in the “fast moving investigation” into the terrorist attack on the Manchester Arena, bringing the total number of arrests to 11 – with nine men still in custody.

Greater Manchester Police arrested the man on Friday evening in connection with Monday’s bombing which killed 22 people following Ariana Grande's concert in Manchester.

“This evening we have arrested a 44-year-old man in the Rusholme area,” police said in a statement.

Latest update pic.twitter.com/f4dF5aUto0 — G M Police (@gmpolice) May 26, 2017

“As it stands eleven people have in total have been arrested in connection with the investigation,” police added.

Authorities are keeping an “open mind” as the “fast-moving” investigation continues, the police added.

Police arrested another man in the Moss Side Area on Friday morning and also conducted a search at an address in the “St. Helens area of Merseyside,” in North West England on Friday.

Two men were arrested in Manchester on Thursday morning. One of them was detained following searches of an address in the Withington area of the city, while the other was arrested in a part of Greater Manchester that was not disclosed. Raids across the area continue.

"I want to reassure people that the arrests that we have made are significant," Greater Manchester Police Chief Constable Ian Hopkins told reporters Thursday.

"These searches will take several days to complete, as you would expect, therefore there will be some disruption. However, it is important that we continue with these searches," Hopkins said. "We are now carrying out associated searches at a number of addresses."

Hospitals across UK told to ‘prepare for further incident’ in wake of #ManchesterBombinghttps://t.co/Km82NS07qApic.twitter.com/5v1XM4lxfU — RT (@RT_com) May 25, 2017

On Monday night, British-born Salman Abedi detonated a “highly sophisticated” nail bomb at Manchester Arena killing 22 people, including young children. Twenty people are still in a critical condition in hospital following Britain’s worst terrorist attack since the 7/7 atrocity 12 years ago.