A string of late-night arsons in Andover charred three homes in one block and a truck a few blocks away, authorities said.

The fires broke out early Tuesday and all “appear to be intentionally set and remain under investigation,” said a statement from the Anoka County Sheriff’s Office.

The first blaze was reported shortly after 1:15 a.m. in a flatbed truck next to a home being built in the 1100 block of 152nd Lane NW. About two hours later, three occupied homes were damaged by the suspicious fires many blocks to the northwest in the 1100 block of 157th Lane NW., the Sheriff’s Office added.

No injuries were reported, and no arrests have been announced.

The Sheriff’s Office said that anyone with information about these blazes should call their investigators at 763-427-1212.