Britain's leading anti-terror police chief has warned the public could be at risk if officers are diverted to fight terrorism.
Metropolitan Police Assistant Commissioner Mark Rowley warned Home Secretary Amber Rudd that counter-terrorism policing was not able to operate at "full strength", in a letter reportedly seen by the BBC.
"The demand for increasing numbers of detectives in areas such as child abuse has prevented this," he reportedly wrote.
He also warned there would be "difficult choices" about where to put resources, according to the BBC.
"It will inevitably push risk to other areas of policing, potentially with significant impact," he reportedly said.
The National Police Chiefs' Council (NPCC) said resources have been "tested" by recent terror attacks.
"We are facing an unprecedented terror threat and it is no surprise that our resources are currently tested against what is now four terrorist attacks and five thwarted plots in very short succession," a spokesman said.
"Police chiefs, within the counter-terrorism network and beyond, have been clear that, while everything is being done to keep people safe, we are facing an extremely challenging period.
"As you would expect, we are having discussions with the Government about police funding in the long term. We are also looking at our resilience over the coming months and have agreed plans across policing to confront the heightened threat and protect our communities."