A baby was taken to hospital after being found injured in a flat in Douglas.
Police have remained at the property on Balunie Avenue this week after the child was taken to Ninewells for treatment.
A Police Scotland spokeswoman said: “We received a report of a baby on Tuesday that had required medical attention after suffering an injury at a property at Balunie Avenue in Dundee.
“The infant was treated at Ninewells Hospital and inquiries are ongoing to establish the full circumstances.”
CID officers have been making door-to-door inquiries at properties in the area.
One resident said: “On Tuesday the CID showed up at the house and on Wednesday they started going door-to-door and asking us questions about what was going on, but we didn’t really know much.
“Having CID come to our door…it’s not normal.
“Since then a police officer has been sat outside the house 24/7, they take it in turns and swap out every few hours.
“They have clearly been told to make sure nobody is going in to the property.
“It just seems concerning.”
Another neighbour, who also declined to be named, added: “We’re a wee bit concerned.
“We kind of want to know what’s going on.
“There’s been someone at the door constantly, they don’t want anyone going in the house at all.
“I think they’re even feeding the cat in there and everything.
“Everyone around here is worried due to the police presence.”