Travis McMichael called police on February 11 at around 7:30 PM to report an unknown "lighter-skinned black male," wearing a red shirt and white pants, was trespassing on a construction site in Brunswick, GA ... this according to a police report obtained by TMZ.

In the report, cops say McMichael told them he saw the black male cut across one property and enter the construction site. McMichael told cops he returned to the property and "observed the unknown male run back through the open house under construction toward the area of the back yard."

Cops responded and searched the property, but no one was there. They say the property owner, Larry English, told them "it appears the unknown male is only trespassing and plundering around as he has yet to see where anything has been taken." Cops say security footage of the incident circulated Facebook and a neighborhood watch app but nobody could identify the unknown black male.

Another neighbor, Diego Perez, says he was also present for the Feb. 11 incident, along with Travis and his father, Gregory, at the February 11 incident. It should be noted ... the police report never mentions Gregory or Diego.

Diego told the Atlanta Journal-Constitution he was there because Larry English -- who was out of town -- sent him the security cam footage, and asked him to go check it out.

But, Perez says he was also on the scene Feb. 23 right after Ahmaud was shot. He claims Ahmaud is the same person the McMichaels confronted 12 days earlier.

As we've reported ... Travis and Gregory were arrested for murder and aggravated assault shortly after the chilling video of Ahmaud's shooting leaked last week.

It's interesting that the younger McMichael described the Feb. 11 trespasser as "lighter-skinned' ... because Ahmaud had a darker complexion.