1 DEAD & 1 WOUNDED @ A BROOKLYN MARINA!

Investigators are hunting for a cold-blooded gunman who calmly shot two men, killing one, after a seemingly minor quarrel at a Brooklyn marina, police said Sunday.
"It was low-key, like they were just shooting the breeze," said a police source. "That's why witnesses said what happened next was so surprising."

The killer opened fire on Michael Mazzara, 37, who was wounded, and Paul Moghab, 33, who was killed, after chatting with them and their friend at the Venice Marina in Sheepshead Bay on Saturday afternoon.

The shooter, who seemed to know Mazzara, struck up a conversation with the men. He then began gesturing at them, but at no point did their fight become loud or violent, witnesses told police.

Suddenly, the man pulled a gun out of his knapsack and fired a single round, hitting Mazzara in the face at point-blank range and causing him to topple off the boat and into the water.

Moghab dove into the water in an attempt to escape, but the shooter simply tracked his movements with the gun and waited for him to come up for air, police said.

When Moghab emerged, the gunman unleashed several more shots, fatally striking him in the chest.

The suspect then dashed across the Belt Parkway and remains at large, police said.

Mazzara's other friend, whom police did not identify, hid on the boat and was not injured.

Witnesses told police the shooter was a white man in his 30s, wearing a light-colored shirt and camouflage shorts.

Mazzara was rushed to Lutheran Medical Center, where he remained in critical condition Sunday.

Investigators said Mazzara served time this decade for attempted robbery and also has been arrested for assault, weapons possession and grand larceny.

It was unclear if his criminal history was connected to the shooting.

Cops were exploring whether the shooter believed Mazzara owed him money or a Jet Ski, police sources said.

One of Mazzara's relatives declined to speak with reporters when reached at the victim's Gravesend, Brooklyn, home.