Construction worker and teen nephew shot on the job after argument with suspect as manhunt launched

Phoenix police have launched a manhunt for a suspect who shot two construction workers on Sunday morning , killing one and leaving the other fighting for his life.

Authorities are asking for the public's help identifying a suspect who allegedly shot and killed 48-year-old Alan David Whitworth and critically injured his 19-year-old nephew, unnamed for safety reasons.

The two were working on a construction project when the suspect began arguing with them, pulling out a gun . The suspect fired multiple shots into both victims, shooting them again when they were on the ground, according to a police report. Whitworth's grieving family says they've been left 'heartbroken' over the loss over a 'loving' husband and father, adding that the teen is a father as well.

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Jeanna Avery, a family member related to both victims, told ABC15 that Whitworth was an upstanding father who just launched his own electrical company and picked up an extra job doing fencing that fateful morning. He was working near 39th Street and Thomas Road when the incident happened.

"He went out at eight o'clock on a Sunday morning, and never thought he would never be coming home," said Avery. Whitworth was due to become her son-in-law and the teen is her nephew.

"There's no reason for senseless acts of violence like this," added Avery. "You don't know who's who you're taking from somebody else, like their fathers, there's sons, there's mothers."

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Whitworth leaves behind a daughter, Mariah Avery, who was too 'heartbroken' to speak. A GoFundMe was launched to help the family deal with the loss. "His life was taken while at work trying to provide for his family. He was loved by many and his smile, laugh & heart will be missed dearly," wrote Avery about Whitworth.

Anyone with information on the suspect or incident is encouraged to call the Phoenix Police Department at 602-262-6151 or Silent Witness at 480-WITNESS. Silent Witness allows callers to remain anonymous and leaves them eligible for a reward.