Both men are suspected of sending money to terrorist groups in Somalia between 2006 and 2008.
The 42-year-old denied the charges and requested he be released, but the court found sufficient reason to keep the man detained.
“The suspicions are stronger. The investigation is moving forward,” said public prosecutor Ronnie Jacobsson to the TT news agency.
According to the court, the prosecutor should bring an indictment on May 5th, but Jacobsson explained that he doubted the case would be ready by that date.
“The investigation isn’t going to be finished by then,” he said.
The 37-year-old, who is a politician for the opposition in Somalia, also denies the charges and wants to be released.
The two men, both of whom are Swedish citizens of Somali origin, were arrested on February 28th. A third man arrested at the time was later released due to insufficient evidence.
The men were among a total of six people arrested as part of coordinated operations between Norway and Sweden.
Swedish Security Service Säpo suspect the two men of having links to the Al-Shabaab organization in Somalia.
Al-Shabaab, which translates roughly as ‘Youth’, is a breakaway faction of the Islamic Courts in Somalia.