WASHINGTON, 24 September 2005 — One of the largest mass evacuations in history took place during the last three days in Texas and Louisiana where as many as three million people fled from Hurricane Rita, scheduled to make landfall early today around the Texas/western Louisiana border.

Yesterday afternoon, Rita was downgraded to a Category 3 storm, with 200 km per hour winds, but is still very dangerous, weather forecasters warned.

Hurricane Rita took an early toll when a bus carrying elderly evacuees from the Houston area burst into flames outside Dallas before dawn, killing at least 24 people trapped inside.

Oxygen tanks used by many passengers exploded as the fire spread. Multiple blasts were heard before the bus became engulfed in flames, lighting the morning sky near a southern suburb of Dallas.

Sheriff’s deputies, the bus driver and even some elderly passengers frantically tried to save people before the blasts started.

“Some of them suffered from smoke inhalation, but they were concerned for their fellow bus passengers,” Sgt. Don Peritz of the Dallas County Sheriff’s Department said.

The bus was carrying 38 residents of the Brighton Gardens of Bellaire home, owned by McLean, Virginia-based Sunrise Senior Living.

The fire shut Interstate 45, a major escape artery for hurricane evacuees from the Houston area going toward Dallas and beyond.

In New Orleans, water spilled over a freshly patched levee into a hard-hit neighborhood as Rita’s outer edge dumped rain on a city left nearly deserted after Hurricane Katrina’s devastation last month. Rising winds shook light buildings as far away as Baton Rouge and tornado warnings were in effect for parts of Louisiana.

“It’s a very bad situation for New Orleans,” said Timothy Schott, a meteorologist with the National Weather Service in Washington. “It’s quite close to the worst case scenario.”

Forecasters warned of a possible coastal storm surge of 15 to 20 feet from the hurricane, with large swells, battering waves and winds, and as much as two feet of rain along the Texas and western Louisiana coasts.

Heavy rains added to the problems of the hundreds of thousands of people who jammed evacuation routes. But highways finally began flowing yesterday near Houston, where Mayor Bill White opened both sides of the highway for those fleeing the city and promised that no one would be left stranded on the highways when the hurricane arrives. “We will make sure that will not happen,” he said.

The Texas and Louisiana coast is home to the country’s biggest concentration of oil refineries, where it is also feared that Rita will cripple the heart of the country’s petrochemical industry.

Environmentalists warned of the possibility of a toxic spill from the 87 chemical plants and petroleum installations that represent more than one-fourth of US refining capacity.

Texas Gov. Rick Perry said state officials had been in contact with plants that are “taking appropriate procedures to safeguard their facilities.”

At Houston’s Johnson Space Center, NASA evacuated its staff, powered down the computers at Mission Control and turned the International Space Station over to the Russian space agency.

President George W. Bush said officials at every level of government “are preparing for the worst” and that the United States has the “resources there to help the federal, state and local officials to respond swiftly and effectively.”