A passenger plane crashed in an ice-covered lake in northern China seconds after takeoff Sunday, killing all 53 people aboard and one person on the ground after an apparent midair explosion, the government said.

The was no immediate word on the cause of the crash, which was the country's deadliest in more than two years and was a setback to China's efforts to improve air safety following a string of accidents in the 1990s.

The China Eastern Airlines (search) plane went down in Baotou, a city in the Inner Mongolia region 330 miles northwest of Beijing, "only about a dozen seconds" after take off at 8:20 a.m., the official Xinhua News Agency said.

The plane, a Bombardier CRJ-200 (search), was headed for Shanghai with 47 passengers and six crew members when it crashed into the lake in Nanhai Park, Xinhua said.

Premier Wen Jiabao ordered all-out efforts to determine the crash's cause, state television reported in its national evening newscast.

All CRJ-200 aircraft in China were grounded, and cabinet-level investigators were dispatched to the crash site from Beijing, Xinhua said.

Witnesses told the agency they heard an explosion before the plane hit the ground, and one described seeing "a big fireball" overhead.

Wang Yongqiang, who lives near the park, said he saw black smoke billowing from the tail of the plane before it crashed and broke into fiery fragments, Xinhua said. He also heard "a big blast" when the plane was still in the air, the agency said.

A house next to the park was damaged and several boats were scorched, it added.

All aboard were confirmed dead — their remains pulled from the lake by emergency workers who had to break through ice on the lake to get to the wreckage, reports said.

The weather in Baotou was clear and cold — about minus 25 degrees.

A worker on the ground at Nanhai Park was also killed, Xinhua said. Early reports said two park workers were killed, but that was later revised to one confirmed death.

One Indonesian was among the passengers killed and the rest were Chinese nationals, the reports said.

Divers were called in to help look for the plane's flight data recorders, or "black boxes."

China suffered numerous deadly plane crashes in the 1990s, prompting the government to tighten safety measures and upgrade airplanes in the completely state-controlled aviation industry.

The nation's last major crash was on May 7, 2002, when a China Northern Airlines MD-82 plunged into the sea off the northeastern port city of Dalian, killing 112 people. Officials blamed arson by a passenger who had taken out seven life insurance policies.