A man has been arrested on suspicion of murdering a 14-year-old boy in a Forest Gate playground in 2017.
Corey Junior Davis was shot in the head in Moore Walk just before 3.10pm on September 4. He died the next day.
The boy, also known as CJ, had been socialising with a friend when the shooting happened, police said.
A Met Police spokesperson has now revealed that a 24-year-old man has been arrested on suspicion of Corey Junior's murder and was released under investigation.
Det Ch Insp Dave Whellams, from the Met's Specialist Crime Command, said: "This is an important development in our investigation and demonstrates our commitment in our pursuit for justice for CJ and his family."
Police made two previous arrests in June 2018 and February 2019, but the spokesperson said both suspects were released without further action.
Detectives investigating the case offered a £20,000 reward in 2020 to anyone who providing information that leads to a conviction.
His mother Keisha McLeod has previously described her son as "a fun, loving, kind and handsome young boy".
The police investigation continues and the Met asked anyone who can help officers to contact the incident room on 020 8345 3775.
Information can also be provided anonymously by calling the independent charity Crimestoppers on 0800 555 111.
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