BALTIMORE (WJZ) — Baltimore County detectives are seeking the public’s help in finding the person who killed Daniel Ho Coverston in 2009, according to authorities.

Detectives want to hear from anyone who spent time near the Alameda Shopping Center where a payphone was located in 2009, police said. 

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Detectives believe it is possible a person made a phone call made from that payphone prior to entering the 22-year-old man’s apartment and killed him as he was recovering from eye surgery, according to authorities.

Coverston’s friend found him deceased inside of his apartment in the 7000 block of Lachlan Circle when he went to check on him around 2:50 p.m. on Valentine’s Day.

Coverston had left the door unlocked because he was expecting his friend, police said.

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The friend had checked on Coverston multiple times since the surgery. Each time, Coverston was following the doctor’s orders by resting on his face, according to authorities.

The only possible clue to the killer’s identity may be in the last phone call he received, which came from the phone booth, police said.

Coverston’s family members remain hopeful that whoever killed their loved one will be brought to justice. 

In 2016 Metro Crime Stoppers announced an increased reward of $15,000 for tips that could lead to the arrest and prosecution of the person who killed Coverston. 

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Anyone with information on the death of Coverston can contact Metro Crime Stoppers at 1-866-7LOCKUP.