Calling for help from the public, Chicago police released a surveillance image of a person in a mask wanted for questioning in the two murders — one of a 73-year-old man walking his dogs on Sunday morning, the other of a 24-year-old man of the Orthodox Jewish faith found dead on the lakefront path Monday.

“This person is clearly trying to disguise themselves,” Chicago Police Supt. Eddie Johnson said at a Tuesday press conference at the 24th District police station. “Clearly he or she knows what they are going out to do.”

The elderly victim, Willard Douglass Watts, was walking his dogs just after 10 a.m. Sunday near his home in the 1400 block of West Sherwin when someone walked up and shot him in the head, according to police and the Cook County medical examiner’s office.

A day and a half later — and about a half-mile down Sheridan Road — Eliyahu Moscowitz was walking on the Loyola Park bike path about 10:20 p.m. Monday near Lunt Avenue when someone shot him in the head behind his ear, authorities said.

Johnson said the investigation is “still in the preliminary stages,” but expedited ballistic tests performed by the ATF confirmed that the shell casings found at the scenes of both shootings came from the same gun.

Police initially said Watts might have been shot during a robbery, but Johnson said Tuesday that nothing was taken from either victim. They did not appear to have any connections.

A possible motive is unknown. Johnson did not rule out the possibility of a hate crime.

“It’s just too early to be able to say that definitively, though we are looking at every possibility,” he said.

Mayor Rahm Emanuel urged neighborhood residents to “go about your daily lives, but be safe, smart and vigilant at the same time.

“Two men, different ages and backgrounds whose lives ended with the same gun used. Their deaths were senseless and tragic,” Emanuel said.

The surveillance image released by police Tuesday came from near the scene of Watts’ killing, showing a person dressed in all-dark clothing with a hooded mask. Police describe him as a black male with a thin build.

“There is someone out there who knows who this person is, whether it’s a family member, a friend, a trusted loved one — we need you to do the right thing and call the police,” Johnson said.

Watts’ shooter took off west on Sherwin and then southbound in the west alley, police said.

Detectives were still reviewing security video and identifying possible witnesses in Moscowitz’s death.

The 24-year-old worked for more than two years as a mashgiach at Jewel-Osco, supervising the preparation of kosher foods.

“Our hearts go out to the family of Eliyahu Moscowitz,” Jewel-Oscco spokeswoman Mary Frances Trucco said in an email. “Eliyahu was also very personable and well-liked by his colleagues.”

Police were adding extra patrols to Rogers Park in the aftermath of the connected killings.

Prior to the murders of Moscowitz and Watts, the Rogers Park neighborhood had recorded two murders and 14 nonfatal shootings in 2018, according to CPD data. Last year, four people were killed and another 11 wounded by gunfire in the North Side neighborhood.

Anyone with information is asked to call detectives at (312) 744-8261, or dial 911. Tips can be left anonymously at cpdtip.com.