Metallsperringer utenfor Buckingham Palace. Men det er umulig å beskytte seg mot mennesker med kniver.
En politimann ble angrepet av en mann med kniv utenfor Ilford-stasjonen i Øst-London lørdag. Det skal ikke være fare for livet.
Police officer has been stabbed in an incident outside an east London railway station.
British Transport Police (BTP) said the male officer was approached by a suspect outside Ilford Station and attacked with a knife.
The officer was taken by ambulance to hospital for treatment for his injuries, which are not thought to life-threatening.
A man has been arrested over the incident, BTP said.
Counter-terrorism police are not involved at this stage, it is understood.
Utad forsøker politiet ikke å hausse opp stemningen, men at det var alvorlig er det ingen tvil. Området ble stengt ned. Øyenvitner forteller om «blod».
Witnesses described seeing the bloodied officer outside the station as it was put on «complete lockdown».
Another tweeted: «At Ilford station… just come outside and all I see is someone on the floor, blood and police.»
Footage shared on social media showed a man being restrained on the floor as more officers arrived.
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