Ealing Broadway was cordoned off after the attack on the officers Detectives are continuing to question a man after two police officers were attacked with a knife – one of them suffering a serious neck wound – as they carried out checks on bus tickets.
The seriously injured officer, a police constable, underwent surgery and is now said to be in a stable condition.
Both men were attacked at a bus stop in New Broadway, Ealing at about 1500 GMT.
A 30-year-old man arrested at the scene is being held at a west London police station. A knife was also recovered.
It is thought they were attacked after it emerged one of the passengers on the bus was wanted for recall to prison.
Ch Supt Andy Rowell commended the officers for their actions “and their bravery and also several members of the public who came to their aid during this incident”.
The 23-year-old police constable and a police community support officer, aged 27, were attacked after challenging a man.
One witness, Koon Midam, said: “The man was asked to show a valid ticket and went into a violent rage.
“Very quickly the problem escalated as he drew his knife and made a few quick slashes.
“It was more of a shock for the first few moments and then there were the cries, the Pc dropping to the floor and the man lashing out again.”
Another witness, a motorist, said he saw two policemen “sprinting to the back of a police car to retrieve a green first aid kit.
“They rushed back to assist a policeman who had blood on him. I then noticed another policeman who was walking slowly and then collapsed on the pavement. His arm fell to his side.”
Councillor Julian Bell, leader of Ealing Council, described it as a “truly shocking incident”.
Council staff are said to be already reviewing CCTV footage from the area.
Police superintendent: “I would like to commend the officers for their bravery”
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