A 10-month old boy has been shot dead in his father’s arms as he was being taken for a walk outside a Houston apartment complex.

Messiah Justice Marshall was being carried by his father at about 1.30pm on Wednesday when three men approached them. According to police, an argument ensued, and one of the suspects fired repeatedly at the baby’s father.

Messiah’s father, who has not been named, tried to escape through a parking lot and came across a passerby who drove them to a nearby gas station, where police and paramedics arrived. The boy died at the scene.

“He was just at the beginning of his journey and his journey was cut short by cowards who have absolutely no respect for the sanctity of life, by cowards that crossed a line. You don’t shoot at a man carrying his 10-month old son,” said Art Acevedo, the Houston police chief.

Acevedo told reporters that the department is searching for three suspects in their early twenties. “There’s lines you cannot cross,” he said at a press conference on Thursday.

The driver who took Messiah and his father to the gas station described the incident to Click2Houston. “[The father] got in the car and we went to the Valero because I saw a cop there earlier. He started screaming, ‘Call an ambulance! Call 911!’ and finally help came,” the driver, Joshua Levy said. “I was a little nervous, my legs started shaking. It’s so sad seeing him walk around with his baby basically dead in his hands.”

Acevedo said that police will step up their presence at the complex in an effort to find the suspects and thwart any future gang activity. “We’re not going to rest until we bring these people into custody,” he said.

Police are investigating if there was any prior contact between the father and the suspects. “Doesn’t matter what motivated them. I don’t care what was going through their minds but they crossed an extremely, extremely clear line,” Acevedo said. “We’re not going to put up with this.”

Messiah is not the only child to die in a Houston-area shooting recently. In March, Houston police arrested a man on suspicion of fatally shooting an eight-year-old girl while she was in a car being driven by her mother that was involved in a traffic accident.

A 14-year-old boy died on Tuesday, a day after he was accidentally shot in the head by his twin brother, who had been aiming at a snake they found in a ditch.

Three weeks ago, and about a mile away from the location where Messiah died, a one-year-old boy in a vehicle survived after being shot in the leg by an unknown assailant in an SUV.