A mother who was knocked to the ground when Manchester Arena bomber Salman Abedi detonated his weapon told an inquiry he was "looking a bit odd" in the moments before the atrocity.
Sarah Nellist had been waiting to collect her teenage daughter and niece, six, from the Ariana Grande concert at the UK's Manchester Arena on May 22, 2017, when terrorist Mr Abedi detonated a bomb, killing 22 people and injuring hundreds.
Ms Nellist is one of the first survivors to give evidence.
The Manchester Arena Inquiry is examining the circumstances of the attack and whether any opportunities to prevent it were missed. It was established by UK Home Secretary Priti Patel in October.
On Monday, Ms Nellist told the hearing that security guards were not searching everyone's bags.
She said she was standing near the box office waiting to collect her daughter and niece when she spotted Mr Abedi.
"He just looked a bit odd," she said.
"There were mums and dads there, I thought maybe he was there for his sister and he didn't want to be there. It was a couple of minutes [before the bomb exploded]."
She said there was no warning about the bomb and she saw it out of the corner of her eye.
"He detonated the bomb, it was like black powder paint. It was just like a high pitch sound and the heat was just unbelievable," she said.
The explosion knocked her out and when she regained consciousness she began a frantic search for her daughter and niece and was reunited with them outside.
The inquiry previously heard that only one paramedic reached the City Room, the scene of the blast, within 40 minutes. That paramedic had travelled on his own initiative and followed a police vehicle to the scene.
Suicide bomber Mr Abedi, 22, died after detonating a rucksack bomb in a foyer area of the arena at the end of the concert.
His younger brother, Hashem Abedi, was convicted last year on 22 counts of murder, one count of attempted murder and one count of conspiracy to cause an explosion.
He was jailed for a minimum of 55 years.
