The teenage couple were apparently overheard declaring their love for each other during a shopping trip to New York earlier this week.
An onlooker in Armani Exchange told PopEater, 'Justin and Selena were holding hands as they shopped and said 'I love you' to each other not once, but several times in public. Everyone could hear them.
'I guess they want to share their love with the world... Justin's bodyguard wouldn't let anyone get too close to them, but that didn't stop them from showing off their affection for each other. They were just in their own world... dazed and in love.'
The romance between the pair is said to have got even more serious when Selena, 18, met Bieber's family earlier this month.