Nobel Peace Prize winner Malala Yousafzai on Thursday expressed sympathy for a Mexican asylum seeker who jumped onto the stage during the award ceremony in Oslo, and said the incident didn't frighten her.

The 17-year-old laureate from Pakistan, who was shot in the head by a Taliban gunman, said young people the world over face problems.

"As [he] was from Mexico, so there are problems in Mexico," she said after meeting Norwegian Prime Minister Erna Solberg. "There are problems even in America, even here in Norway, and it is really important that children raise their voices."

Oslo police said the flag-waving 21-year-old, who has applied for political asylum in Norway, was fined 15,000 kroner ($2,100) for disturbing the peace and sent back to an asylum center.

Malala told reporters she was not afraid when the intruder stepped out in front of her and co-winner Kailash Satyarthi as they were holding up their award certificates and medals in front of hundreds of guests, including Norwegian royalty and politicians.

"If I don't get scared at anything else why would I get scared of this," she said, laughing. "There was nothing to be scared of."

The man was quickly whisked away by a security guard but police were unable to explain how he had managed to enter Oslo City Hall without an invitation amid tight security in the city.

Police said they did not know the motive of the intruder, identified to The Associated Press as Adan Cortes Salas by his brother in Mexico.

Malala, the youngest ever Nobel Prize winner, shared the $1.1 million award with the 60-year-old Indian for helping protect children from slavery, extremism and forced labor, and advance their education.