At least 49 people have been killed in fast-moving wildfires outside Athens, officials said Tuesday. As thousands of tourists and residents found evacuation routes blocked by flames, some took to rickety boats to escape.

Gale-force winds, topping more than 50 miles per hour, fanned a pair of fires that tore their way through an area popular with travelers, injuring more than 150 people and leaving a trail of charred resorts, burned-out cars and smoldering farms in their wake.

Greece’s emergency services were stretched to capacity, as more than 600 firefighters were deployed to the sites of the two largest fires, in Rafina, east of Athens, and Kineta to the west. The country’s entire fleet of water-dropping aircraft was deployed on Monday, and officials called on their partners in the European Union for help.

Whole towns were destroyed, locals said, and officials warned that the death toll would rise as emergency workers cleared burned homes and cars, in which some evacuees had become trapped.

“Mati doesn’t even exist as a settlement anymore,” a resident told Skai TV. “I saw corpses, burned-out cars. I feel lucky to be alive.”

Roads into Athens were choked by residents trying to flee, hampering rescuers’ efforts to reach the fires. Penned in by the flames, some looked to the sea to escape, hitching rides on passing fishing boats or resorting to makeshift rafts before the navy began an organized evacuation.

Escaping by sea, however, posed its own deadly challenge: The Greek Coast Guard said it recovered the bodies of at least four evacuees.

On Monday, Prime Minister Alexis Tsipras cut short an official visit to Croatia.

“It’s a difficult night for Greece,” Mr. Tsipras said. “We are dealing with something completely asymmetric.”

Wildfires are an annual occurrence in the hot, dry summer months. But a drought and a recent heat wave, which saw temperatures exceed 100 degrees Fahrenheit, have fueled these fires, Greece’s deadliest in more than a decade. Sixty people were killed in a 2007 blaze that swept through the country’s Peloponnese region.

The fires have so far skirted Athens, leaving the city’s ancient ruins unscathed. The blaze, however, could be seen from the capital and bits of ash fell on the city.