What Is Portcullis House? The Westminster Bridge Attack Shut Down Nearby Parliament

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There were multiple reports of a shooting Wednesday near Portcullis House in London. The Metropolitan Police of London verified that officers responded to a call for help in the aftermath of a "firearms incident." Police were dispatched to the nearby Westminster Bridge, and the BBC has reportedly shown photos of people being treated for wounds on the bridge itself.

Portcullis House is currently on lockdown. The building holds offices for Parliament members, as well as their staff. According to the most recent reporting from The Guardian, a police officer was stabbed outside of Portcullis House, and the man believed to be the perpetrator has been shot. A statement by David Lidington, the Leader of the House of Commons, read:

"What I am able to say to the House is that there has been a serious incident within the estate. It seems that a police officer has been stabbed; that the alleged assailant was shot by armed police. An air ambulance is attending the scene to remove the casualties. There are also reports of further violent incidents in the vicinity."

According to Vikram Dodd, also reporting at The Guardian, "The early police view emerging from the chaos is there were probably two sites of attack. Westminster Bridge where people may have been run over. Parliament itself where appears officer stabbed and attacker shot." Additionally, it's reported that Prime Minister Theresa May was rushed into a car very close to Parliament, in the immediate aftermath of the police stabbing that occurred close by outside of Portcullis House.

The Westminster tube station (London's subway system) has been closed. Portcullis House was built in conjunction with the newly renovated Westminster stop, completed in 2001.

London police are now treating these events as acts of terrorism. As such, all tourists are being asked to leave the corresponding areas, with some officers implying to reporters that the situation could be ongoing. Some estimates place the number of people injured on the Westminster Bridge as high as a dozen.

More information will be made available as it is verified. As of now, we know that there was a knife attack on an officer outside of Portcullis House, and that the attacker has been shot. We also know that there appears to be an intentional car attack on civilians walking across Westminster Bridge.

More to come ...