At least 29 passengers riding on an Indonesian ferry have died after the vessel sank in choppy waters off the island of Sumatra, officials said Sunday.

Rescue crews managed to save 245 passengers of the Dumai Express 10 before calling off the search after nightfall. However, that has left 17 other passengers still missing.

At the peak of the search Sunday, nine ships and a number of fishing boats were on the water looking for survivors.

One survivor, identified only as Riki, told official news agency Antara that he broke a window in order to escape the sinking vessel and was rescued by passing fishermen.

"It was too fast ... and the ship crew did not tell us about the situation at all," he said. "We only managed to get out after I broke the glass window on the right side. That was the only way because there were many people jostling for the doors."

But high waves hampered the rescue operation.

Local police Chief Yasin Kosasih said crews will resume the search Monday because conditions are just too dangerous for rescuers.

"Considering the weather condition and the dark, we ... will resume the search tomorrow morning," Kosasih said.

According to Kosasih, two of the bodies recovered were those of children.

It is unclear how many passengers were on the Dumai Express. Police and navy officials said the manifest indicated 228 people, including 15 children, as well as 13 crew members.

But the number of people located has already surpassed that total. The vessel had a capacity of 273 people.

The ferry had left Batam on Sunday morning for Dumai in the province of Riau, off Sumatra.

The vessel hit stormy weather and rough seas about 90 minutes into its trip and sank about 30 minutes after waves hit its bow and it began taking on water.

Other boats in the area rescued passengers and transported them to nearby islands for medical treatment.

Meanwhile, a second ferry ran aground in the rough seas and was still stranded late Sunday night.

The Dumai Express 15 ran aground while en route from Batam to Moro island in Sumatra.

Kosasih said all 278 passengers from that vessel are safe.

Accidents on ferries, which are a popular mode of transportation between Indonesia's 17,000 islands, are common due to weak regulations and overcrowding.

In January, 230 people went missing after a ferry capsized amid a cyclone off the western coast of Sulawesi.

In December 2006, more than 400 people were killed when their overcrowded ferry broke up and sank in the Java Sea in stormy weather.

With files from The Associated Press