The man, who hails from Manipur, has tried to enter the American embassy on earlier occasions as well, they added.
He told police that since he is mentally ill, he felt that he would be able to get the right kind of treatment in the US and would be fully cured.
In August last year also, he had reached the embassy and tried to enter it but was caught by the police.
His parents, who stay in Manipur, were informed and they came to Delhi and took him with them, the officer said.
His sister works in a private firm in Bangalore while his mother has a clerical job at the governor's office in Manipur, he added.
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