Emma Watson stopped by US border officials

According to The Sunday People, the 22-year-old 'Harry Potter' star singled out after landing at New York's JFK airport and told she should be accompanied by an adult.

The flustered actress, who was eventually waved through and managed to laugh off the incident, later revealed that she is often mistaken for a kid and blamed the fact she was wearing a schoolgirl-style backpack.

According to a source, Watson was mortified, and not only did they not recognise her, they thought she was a child. It was very embarrassing but she managed to awkwardly laugh it off.

The British actress, who recently finished filming her latest movie 'This Is The End', later told of her embarrassment on Twitter.

"Passport control: 'Unaccompanied minor?' Me: 'Sorry?' Passport control: 'Where is ur guardian?' Me: 'I'm 22!!!!!!!' #neverwearingabackpackagain," the Mirror quoted her as tweeting.

"The really sad thing is that this is not the first time this has happened," she added.

The star was returning to the US where she was expected to continue her studies at Brown University, Rhode Island.

Emma Watson 'embarrassed' by early Potter films

Emma Watson feels like a "different person" to the girl in the early 'Harry Potter' films.

The 21-year-old actress -- who was just nine-years-old when she appeared as Hermione Granger in the first movie in the franchise, 'Harry Potter and the Philosopher's Stone' -- finds it "embarrassing" to look back on her early performances because she has changed so much.

Speaking ahead of the release on the eighth and final film in the series, 'Harry Potter and the Deathly Hallows Part 2' she told the Daily Telegraph newspaper: "I look back at the early films and see that little girl, and I know it's me, but it seems like a different person.

"It's somewhat embarrassing to see myself go through all the awkward stages of growing up. So much time has passed and so much has happened that it seems that I don't know her, but it's interesting to see how the character has evolved and how much I have changed."

Since completing filming on the series wrapped last year, Emma, now 21, has moved on, studying at university and signing up to appear in 'My Week with Marilyn' and 'The Perks of Being a Wallflower', but her cast mate Rupert Grint has admitted he's found it harder to move on.

He said: "I loved every minute of it, and I'm really going to miss it. I felt empty and a bit lost, and it's taken me a while to accept it's over.

"When Harry Potter started, I wanted to be an ice-cream man, but the films showed me that I wanted to be an actor, although for the first three I didn't take it very seriously. I just stood where I was told and read my lines. Then with the fourth film I started caring more about my performance."

'Harry Potter and the Deathly Hallows -- Part 2' had its world premiere in London Thursday night.