A school in Sydney’s city centre has endured a frightening start to the week, with a man arrested over allegedly threatening staff.

Police were called to St Andrew’s Cathedral School at about 9.45am on Monday following reports alleging the 46-year-old man had made threats towards staff before reappearing on school grounds.

The school, located on the corner of Druitt and Kent Streets in Sydney’s CBD, was placed in lockdown as officers searched the building with help from specialist police.

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The man could not be found during the search and the lockdown was lifted at about 11am.

It is alleged he was later spotted acting erratically and refusing to leave a hotel in Surry Hills, where he was arrested about 12pm.

“Following inquiries, police identified the man as being wanted in relation to the earlier incident at the school,” police said.

The school said in the afternoon that a “disorientated man” entered the school briefly.

He “was off site less than a minute later”, said a spokesperson.

“Out of an abundance of caution, a lockdown was instituted immediately, and a full sweep of the building was conducted by the NSW Police.”

The school confirmed that there was no threat of violence and no one was harmed.

St Andrew’s Cathedral School was rocked in October 2023, when 21-year-old water polo coach Lilie James was found dead in a campus bathroom.

She had been beaten to death with a hammer by her colleague, Paul Thijssen, whom she had briefly dated.

Thijssen took his own life later in Sydney’s eastern suburbs.