Eastern Star, the cruise ship that capsized in the Yangtze river with more than 450 people aboard, was cited for safety violations two years ago, records from a Chinese maritime agency show.

Authorities in Nanjing, where the Eastern Star began its unfortunate voyage, held the ship and five other Yangtze cruise vessels for violating standards during a safety inspection campaign in 2013, according to a report on the city's Maritime Safety website.

The report provided only sketchy details. Among the dozens of violations among the vessels were practices such as failing to use the ship's automated identification systems. It didn't break down the violations by individual vessel or say who owned the other vessels.

Authorities are bound to scrutinize the Eastern Star's safety record and that of its owner, Chongqing Eastern Shipping Corp., as they investigate why the ship capsized late Monday. Police have detained the ship's captain and chief engineer, who were among the few survivors.

Chongqing Eastern Shipping is one of China's oldest pleasure cruise companies, struggling to compete with newcomers offering much fancier accommodations.

For decades, the sunken Eastern Star, the Eastern Pearl and other "three-star" cruise ships have made the 1,100 mile (1,800-kilometre) journey from Chongqing, perched high above the Yangtze, past the craggy, scenic Three Gorges and their gargantuan dam, to Nanjing, way down in the swampy lowlands.

According to state media, Chongqing Eastern Shipping was founded in 1967 during the tumult of the 1966-76 Cultural Revolution as a state company handling river cargo transport from the upper reaches of the Yangtze to the sea. Since the early 1990s it also has run cruise ships, mostly relatively basic vessels with tiny cabins and toilets that double as shower stalls.

Operators of the flat-bottomed, multi-decked ships charge their mostly older, Chinese passengers modest fares of 1,000 yuan ($160) and up for three- to five-day tours, most meals included. The boats ply a river that is often difficult to navigate and the industry as a whole struggles to find qualified staff, at least partly because of low salaries.

Although the cause of the Eastern Star's capsize is still under investigation and may have come during bad weather, ships in the company's aging fleet have run into problems in the past. The Eastern Prince, a similar vessel, was stranded on a shoal in May 2000 with 436 passengers and crew aboard. All were safely rescued and the boat was retrieved and returned to service.

In 2008 the Eastern Prince collided with an oil tanker on the river, according to a maritime safety report that concluded that while crews of both boats had not violated regulations there was a need for improved training and safety.

On Thursday, rescuers escalated efforts to retrieve missing people from the Eastern Star, which sits upside down in the middle stretch of the river.

Rescuers cut through the hull of the ship and pulled out 39 drowned passengers, bringing the death toll to 65. Only 14 people are known to have survived.

The 2,200 gross-ton vessel, built in 1994, is 250 feet (76.5 metres) long and carries a maximum of 534 passengers.

The newer cruise lines have larger ships with mostly smaller passenger loads: the 10,680-ton Victoria Jenna, inaugurated in 2009, is 440 feet (134 metres) long and carries up to 378 passengers.

The fancier vessels generally offer amenities such as private balconies, fully equipped bathrooms, fitness facilities, Internet access and cable television.

The flow of tourists through the Three Gorges area peaked with a rush to see sites due to be inundated before the completion of the giant dam in 2012.

Enough historic and cultural sites remain to ensure a steady stream of tourists eager to escape busy cities for a leisurely cruise on the Yangtze's turbid brown waters. But the numbers of passengers have been decreasing and the construction of expressways and high-speed railways is reducing demand, putting further pressure on the passenger travel industry.

Cruise operators are also having trouble finding qualified staff, according to a report by the official Xinhua News Agency, which said that a ship technician's salary tends to be lower than that of an auto mechanic.

According to state-run newspaper China Business Journal, Chongqing Eastern Shipping reported net profit of only 1.3 million yuan (about $210,000) in 2014. It had liabilities of 184.7 million yuan ($29.8 million) and 89.75 million yuan ($14.5 million) in assets.

It described the company's situation as "rather dismal."

Local media reports showed relatives of passengers and crew gathered at the company's offices in Wanzhou, the city near Chongqing where it is headquartered. They said top executives of the company rushed to the accident site soon after hearing of the disaster.

The Yangtze is a vital link between China's coasts and its resource-rich inland regions, busy with barges and other shipping as well as passenger cruises.

The Yangtze River Administration announced plans this spring to re-inspect all the ships operating through its waterways, to ensure they were water-worthy and stable.

That came after it reported 18 accidents between October and December, including eight collisions, three strandings, five boats sunk and two other accidents, that killed as many as 10 people.