A top aide to the home secretary was escorted out of a bar in the Houses of Parliament by armed police on Tuesday night, just as MPs were voting on an election that Boris Johnson wants to make about law and order.

Two people who witnessed the incident said Priti Patel’s chief of staff, James Starkie, was ordered out of Strangers’ Bar, which is frequented by MPs, after swearing loudly in the vicinity of the Conservative MP Bob Stewart, being refused service and appearing to punch a door.

As he was escorted out by police, witnesses said he apologised for his behaviour. The incident came as MPs finally resolved to break the Brexit deadlock by voting for a general election which is is expected to be held on 12 December.

Starkie is a familiar face around Westminster as a former Vote Leave campaigner who worked for Michael Gove before resigning from the government last November over Theresa May’s Brexit deal.

He later returned to be a senior adviser in the Home Office. Patel told the Conservative annual conference in Manchester earlier this month that the party was taking “its rightful place as the party of law and order in Britain once again”.

A House of Commons spokesperson said: “We can confirm there was an incident with an individual in Strangers’ Bar. The individual was asked to leave and was escorted from the estate by parliamentary security.”

It is not the first time this year the Conservative party has had issues with senior figures causing concern for security. The Tory MP Sir Geoffrey Clifton-Brown was asked to leave the party conference after police were called to an incident in which he allegedly behaved in a manner described by a party spokesman as “totally unacceptable”.

Police said the 66-year-old MP attempted to bring someone into the international lounge who did not have a relevant pass and he was understood to have then remonstrated with a member of staff. Security then intervened. Paramedics were in attendance and security staff shut down entrances and exits into the media lounge and covered the glass window leading into the lounge for about 30 minutes.

In June, the Tory MP Mark Field was suspended as a Foreign Office minister after a video showed him pushing a female Greenpeace activist against a pillar and grabbing her neck when she protested at a Mansion House speech by the then chancellor, Philip Hammond.

When he took over as prime minister, Johnson sacked Field from his ministerial role but also dropped a Whitehall investigation into the manhandling of the protester, Janet Barker. This month, the MP for the Cities of London and Westminster announced he would not stand in the next general election because of the “fractious and febrile” political atmosphere over Brexit.