At least 100 tourists have been forced to evacuate from a coastal area in Montenegro that has been the hardest hit by the blaze. Fueled by strong winds and dry weather, the fire on the Lustica peninsula in southern Montenegro has spread near to homes and camping zones.
"Our forces are not enough to put out a fire of such proportion," said Stevan Katic, the head of Herceg Novi municipality.
The state Montenegrin TV reported that the Interior Ministry asked for international help through the European Union disaster relief system. The navy also stepped in to help evacuate the area by sea, officials said.
Emergency services said strong winds are hampering firefighters' efforts to save the houses.
"The fire has spread over the road, an entire hill is burning," emergency official Maksim Mandic told Montenegrin TV. "It is impossible to put out the fire completely in such winds."
Further north in Croatia, firefighters have also been battling a number of fires along the Adriatic coast. Several hundred acres of pine forests and low shrubbery have been burnt, with the winds sending the blaze spreading in several directions.
Fires around Srinjine, near the coastal town of Split, forced tourists to leave the area, which was left without electricity or water, Croatian TV said.
Several houses and offices were destroyed, as well as the local kindergarten, part of the cemetery and the surrounding olive groves. A man has died in a nearby village but it was not clear whether his death was directly related to the fire, the state TV said.
Firefighting planes took off Monday afternoon after previously being grounded due to winds and turbulence.
Around the town of Zadar, planes were also used because some areas remain mined from the war of the 1990s, it added.