Investigators removed dozens of bizarre items from the Long Island home of suspected Gilgo Beach serial killer Rex Heuermann Monday, including what appeared to be a creepy portrait of a woman with a battered face.

Heuermann was arrested Thursday for the murders of three women whose bodies were found dumped near Gilgo Beach 13 years ago. Police continue to search for clues to link him to more unsolved killings in the area.

Gloved officers were spotted by The Post at the Massapequa Park house of the suspect on Monday while removing a Playboy magazine, film negatives, a poster from the TV show “MAS*H,” and the macabre painting.

The disturbing artwork taken by police features a blond woman’s face with dark pupils and bruising below the eyes.

Earlier in the day and over the weekend, authorities removed a massive trove of up to 300 firearms from a locked vault in the basement of the home. Heuermann — a 59-year-old married father and New York City architect — had permits for just 92 and was known to be an avid hunter, according to CNN.

The latest objects investigators boxed up and towed out of the alleged killer’s family home add to a growling list of strange items. On Saturday, cops carried a child-sized doll contained in a large wooden and glass case from the house as well as cat food, a scratching post, an empty bookcase and a framed picture.

On Friday, police towed away a cooler from the property.

Heuermann’s home — which he grew up in before raising his own family there — was described as “a very cluttered house” by Suffolk County Police Commissioner Rodney Harrison.

Harrison told WPIX11 that the suspected killer “was like a pack rat” and investigators are therefore searching for any “trophies” he might have kept from his slaughters to add to the mounting evidence against him.

Authorities are also searching an Amityville storage unit linked to Heuermann for human remains or so-called trophies.

The married dad was charged with murder in the deaths of Melissa Barthelemy, 24, Megan Waterman, 22, and Amber Costello, 27, whose remains were all found within days of one another in 2010.

Heuermann is also the prime suspect in the death of 25-year-old Maureen Brainard-Barnes, with the victims collectively known as the “Gilgo Four.” Their bodies were among 11 corpses found near each other at the Gilgo Beach site.

Suspected serial killer Rex Heuermann — a New York City architect and married dad of two — was arrested in connection with the long-unsolved Gilgo Beach murders. The arrest is tied to the so-called “Gilgo Four,” women found wrapped in burlap within days of each other in late 2010.

The years-long investigation that led to the arrest revolved around the discovery of more than 10 sets of human remains along Ocean Parkway near Gilgo Beach in Suffolk County between December 2010 and April 2011.

Most victims were petite female sex workers with green or hazel eyes. But there were also two exceptions: a 2-year-old girl and a young Asian man.

The suspect was linked to the 2010 killings after cops obtained his DNA from discarded pizza crust — which they then matched to DNA found on one of the victim’s bodies.

Heuermann is being held without bail while police continue to search for more evidence in the former cold case.