A teenage boy is fighting for his life after being stabbed near the grounds of Barking Abbey.
Officers were called to North Street at 7.24pm on Monday (November 11) following reports of the stabbing.
A Met spokeswoman said: "The police and paramedics arrived to find a teenage boy suffering from a stab wound.
"He was taken to hospital where police await an update on his condition."
One shop worker said he had closed the store in nearby East Street at 8pm to find police with dogs searching the area.
The man, who wished to remain anonymous, added: "We don't know when the police came but when we closed we saw the tape.
"They had dogs and everything in the roads and were checking the area."
A police cordon manned by uniformed officers was in place around a large area of the park between St Joseph's Primary School and St Margaret's Church this morning (Tuesday, November 12).
The church said on its Facebook page: "Owing to an ongoing police investigation, St Margaret's Church and Centre will remain closed for the day.
"Our thoughts and prayers are with both the young man who was the victim of a knife attack last night, and his family and friends."
Three people have been arrested and taken into police custody. Enquiries are continuing.
Anyone with information should call police on 101 or Crimestoppers on 0800 555 111.
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