They are suspected of having transported five hand grenades and of having thrown two of them towards an address in Hellerup north of Copenhagen, where the Israeli embassy is located.
An important part of the investigation will be to examine whether the motive was to carry out a terrorist attack, said prosecutor Søren Harbo to the media before the detention hearing.
Both Swedes deny the crime. When they receive the detention order, they look downcast. They shake hands with their lawyers and are then led out of the courtroom by the police.
Both come from Stockholm County and are previously unconvicted, according to information from TT.
Material Damage
No one was injured, but there was material damage to a building near the embassy.
The prosecutor did not want to comment on whether the two teenagers, 16 and 19 years old, had collaborated with anyone, nor whether there was any suspected link to criminal gangs.
The fact that the teenagers had hand grenades with them in a public environment is a circumstance that risks a harsher sentence.
We have a provision that means that if you have explosives in a public place, and not just at home, it is a particularly aggravating circumstance, says the prosecutor to TT.
Shooting in Stockholm
On Tuesday evening, a shooting occurred at the Israeli embassy in Stockholm. No one has been arrested for the incident, which is being investigated as gross weapons offense, endangering the safety of others, gross unlawful threat, and vandalism.
There is no detention for that offense. Both a crime scene investigation and interviews with people who may have made observations are being conducted, says prosecutor Rasmus Öhman.
At a press conference on Thursday, Fredrik Hallström, operational chief at the Security Police, was asked whether Iran could be involved in the actions now targeting Israeli embassies.
There are some indications that it could be so. But it is an assumption rather than actual knowledge, he says.
Corrected: An incorrect statement that the teenagers had hand grenades with them when they were arrested at Copenhagen Central Station has been removed.