Armed police are currently at the scene of an ongoing incident at a Bonnyrigg industrial estate.
They have locked down Poltonhall industrial estate on Polton Drive, with undercover police vehicles and numerous armed officers at the scene.
One eyewitness, who wishes to remain anonymous, told our sister paper the Edinburgh Evening News: “There is armed police on every corner of the industrial estate, they’re pushing folk away.
“There are around three police vans and numerous undercover vehicles currently on the scene.
The Evening News understands the operation is part of ongoing inquiries into organised crime.
This is the second time in six months the industrial estate has been subject to police raids.
In November 2018, a police helicopter was deployed to assist in a serious crime inquiry.
A Police Scotland spokesperson said: “Police Scotland executed search warrants at a home in Pinkie Drive, Musselburgh and at the Polton Hall Industrial Estate in Midlothian on Tuesday, May 7 as part of an ongoing organised crime investigation.
“Local officers were supported by specialist resources and one man has been arrested.
“Inquiries at both addresses are continuing.”