Malia Obama's 'longtime stalker' begs her to marry him at her internship.

A 30-year-old man who has allegedly been stalking the oldest daughter of former US President Barack Obama has been reported to police.

According to the New York Daily News, Brooklyn resident Jair Nilton Cardoso was detained by the Secret Service after he was accused of stalking and harassing 18-year-old Malia Obama.

Reports suggest Cardoso is a "longtime stalker" who once tried to break into the White House while the Obama family were living there.

Sources say Cardoso found Malia where she was interning in Tribeca, Manhattan, on April 10, and put a sign on the window begging her to marry him.

Two days later, he followed Malia to another one of her internships. He was told to leave by two U.S. Secret Service agents.

The next day, the Secret Service agents interviewed the man at his Brooklyn apartment. Afterwards, he was taken to a Brooklyn hospital for evaluation after the agents determined he had psychiatric issues.

On Tuesday this week, the agents reported the man to NYPD, who are now considering whether to file stalking of harassment charges against the man.

The eldest daughter of Obama has been living in New York City while she completes an internship, rumoured to be with legendary film producer Harvey Weinstein.

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