On Tuesday, a 13-year-old boy was found near Uppsala's main transit terminal. He claimed to be from Afghanistan, explaining that he had come to Sweden via Iran.
"He's doing well considering the circumstances, but he's clearly been affected by the situation," Uppsala police spokesman Christer Nordström told the TT news agency.
Tuesday's incident comes just two days after concerned commuters alerted police on Sunday of a boy who didn't speak Swedish crying outside the transit terminal.
Patrols arrived to discover a 10-year-old boy alone outside the station. After police flagged down a passer-by who spoke Dari, they learned the boy was from Afghanistan.
"He didn't know where he was, but he had been dropped off there," police spokesman Torbjörn Karlsson told the Upsala Nya Tidning (UNT) newspaper.
Police launched an investigation into suspected people smuggling following the discovery of the 10-year-old boy and both boys are now in the care of social services.
The Swedish Migration Board (Migrationsverket) has also been notified in case the boys want to seek asylum.
According to Swedish migration authorities, the average age of unaccompanied minors who come to Sweden is between 15 and 16 years old.
Often times, they contact the Migration Board on their own initiative.
"Most of them come to our offices or have been dropped off outside the door, but it's just as likely they are found alone," Ronnie Magnusson, an expert at the Migration Board, told TT.
In 2011, around 20 young people from Afghanistan turned up in Västerås in central Sweden, many carrying notes bearing the name of the town.
"No one knew why. After a while, they stopped coming there," said Magnusson.
Nordström of the police in Uppsala told UNT it remains unclear if there is any connection between the two boys found alone at the city's main transit station.
"We can't rule out that more unaccompanied children might arrive here," he said.
"It's a tragic story."