There has been a spike in hate crime in the wake of Monday's arena bombing, Greater Manchester Police's chief constable said.
A total of 56 hate crimes were recorded by the force on Wednesday, a significant rise on the 28 reported on Monday, Ian Hopkins said.
The police chief urged the city to remain united after the assault on Manchester Arena left 22 people, including seven children, dead.
He added: "Whilst we can't directly link this to the events of Monday night, we are continuing to monitor the situation and support our communities."
It was feared that another attack on British soil from a suspected Islamist group would spark a backlash against the religious community in the city.
The chief constable continued: "Manchester has come together this week, the public has seen that, they have seen that compassion.
"But it is important that we continue to stand together here, in Greater Manchester.
"Particularly standing together against some of the hateful views that we have seen from a very small minority of the community that have no place here in Greater Manchester.
"Sadly, we've seen an increase in reports of hate crime from 28 on Monday - which is our normal average for a day - through to 56 on Wednesday."
He added: "I have sent a personal message out to all the faith leaders and places of worship today and have thanked them for the support they have shown and stressed that hate crime will not be tolerated."
Mr Hopkins said eight people were in custody, aged between 18 and 38.
They include a man arrested in Wigan on Wednesday afternoon
There are still 12 locations being searched and activity will continue throughout the weekend. The cordon remains around Manchester Arena.
He said: "We have hundreds of officers that are working on this investigation from across the national counter terrorism policing network and we have seized thousands of exhibits that are now being assessed."