Chilling surveillance photos show Manchester bomber at shopping mall days before attack

Chilling surveillance photos have surfaced showing the Manchester Arena suicide bomber shopping at an area mall just three days before Monday night's deadly terrorist attack.

Salman Abedi, the 22-year-old Islamic extremist who killed at least 22 people including children at an Ariana Grande concert, can be seen in the newly released images carrying the Karrimor backpack that was found in pieces at the scene of the bombing.

Photos show supplies used by Manchester arena attacker:

Since the deadly attack, police have announced seven arrests in connection to the case, including many of the bomber's family members.

Abedi's younger brother, Hashem, was arrested on Wednesday in Tripoli, Libya, on suspicion of ties to the Islamic State, according to a spokesman for a local counter-terrorism force.

Authorities also said he was suspected of plotting an attack in the Libyan capital.

Ramadan Abedi, father of Salman and Hashem and outspoken supporter of al-Qaida, was also detained outside his home in Tripoli on Wednesday.

Ramadan told a Tripoli counterterrorism force that he did not expect the attack, and that when Salman left home he told his family he was going on pilgrimage to Mecca.

"I spoke to him about five days ago ... there was nothing wrong, everything was normal," he said in an interview.

Salman Abedi and Hashem, both of whom were British-born, flew from their home in Manchester to Libya on April 17.

Salman returned alone exactly on month later on May 17 to carry out the attack after a brief stopover in Dusseldorf, Germany, a hotbed of Islamic extremism.

SEE: Queen Elizabeth II visits Manchester victims: