An Iranian court has sentenced two Swedish men to three years in prison for photographing military facilities.
According to Swedish media, the men took pictures of military buildings on Qeshm, an Iranian island.
A Swedish newspaper identified them as construction workers from western Sweden, between 30 and 40 years old.
The Swedish foreign ministry earlier said its embassy in Tehran was "working intensively" to secure the pair's release, the AFP news agency reported.
The men appeared in court on 22 April at Bandar Abbas, a city on the mainland north of Qeshm, the Swedish news agency TT said.
It was not immediately clear what their charges were.
The case follows the arrest of a French man and German man who went out on a sailing trip from the United Arab Emirates last November.
They say they mistakenly strayed into Iranian waters because the map they were using showed the disputed islands in the area as Arab, not Iranian.
The two were sentenced in March to 18 months in jail, and intensive diplomatic efforts and appeals from their families have yet to have any effect.
Last year a British husband and wife were detained after mistakenly entering Iranian waters on a similar sailing trip but they were sent home.