A 14-year-old couple reported missing from Sydney is believed to have headed to the Blue Mountains or Lithgow area, according to police.
Lucas Bollard and Sophie McGregor, both 14, have been in a relationship for the past three months and have not been seen since Saturday, May 12, police said in a statement.
Lucas' parents raised the alarm after finding a note left by the teenager.
"It appears the pair have packed their bags and run away together, causing significant concern for their parents," the police statement said.
"Botany Bay police have reason to believe the couple may be heading towards the Blue Mountains or Lithgow area, and are asking anyone who may come in contact with the teens to notify police."
Lucas is described as Caucasian, about 183cm tall with a slim build, short brown hair and brown eyes. He was last seen wearing blue jeans with white sneakers and a grey 'Hurley' brand hoodie.
Sophie is described as Caucasian in appearance, about 152cm tall with a slim build, green eyes and shoulder length black dyed hair.
She was last seen wearing black jeans with black boots, a white t-shirt and a grey jumper with a black cartoon picture on the front. She was also carrying a small green fabric-style backpack.
Police and family of the missing couple hold concern for their welfare due to their young age.
Anyone with information about the couple's whereabouts should contact Botany Bay Police on 8338-7399, or Crime Stoppers on 1800 333 000.