Police operation under way after explosion in Cologne, Bild reports

The police are carrying out an operation in Cologne after an explosion in the city center.

Bild reports that the explosion happened at around 10:30 am on Tuesday morning.

The police have cordoned off the area and are asking people to avoid the city center.

There are no reports of any injuries at this time.

The cause of the explosion is not yet known, but the police are investigating.

We will update this story as more information becomes available.

What we know so far:

• An explosion happened in Cologne, Germany at around 10:30 am on Tuesday morning.

• The police are carrying out an operation in the area.

• There are no reports of any injuries at this time.

• The cause of the explosion is not yet known.

What we don't know:

• What caused the explosion?

• Are there any injuries?

• How long will the police operation last?

We will continue to update this story as more information becomes available.