According to the book Art of War by Sun Tzu, "speed is the soul of warfare".

And it seems the People's Liberation Army is taking note, as it handles rescue and relief operations in Sichuan.

The PLA's General Staff Headquarters (GSH) on Wednesday dispatched 30,000 troops to quake-hit areas in the province, adding to the 50,000 already there.

A soldier carries a wounded child as she is rescued after an earthquake in Beichuan, Sichuan province May 13, 2008. China poured more troops into the earthquake-ravaged province of Sichuan on Wednesday to quicken a search for survivors. [Agencies]

On Tuesday, the Army mobilized 22 military aircraft and 12 civilian planes to ferry 11,420 troops to Sichuan, setting a PLA record in terms of the amount of resources devoted to an air transport mission in a single day.

In the main quake-hit cities, including Dujiangyan, Mianyang and Deyang, soldiers and armed police are racing against time to clear debris, search for survivors, distribute relief materials and maintain order.

Soldiers rescue a child from the rubble at the earthquake-hit Beichuan County, about 160 kilometers northeast of the epicenter of Wenchuan County, Sichuan Province, May 13, 2008.  [Agencies]

The Chengdu Military Command, which covers Sichuan and its neighboring provinces, has also started parachuting relief materials into the worst hit regions despite the volatile weather.

"This is a special time, people are suffering. The Army has to take risks," Li Shiming, commander in chief of the Chengdu Command, said.

As of Wednesday evening, about 1,000 soldiers and 800 armed police troops had reached Wenchuan county, the epicenter of the quake, to carry out relief efforts.

As the only road linking it to the rest of the province has been wiped out, most of the troops moved in on foot over muddy mountain paths, while a few arrived by helicopter and boat.

In response to a complaint the military had arrived too late, a source with the General Staff Headquarters said the Army had marched to the heart of the disaster "in an efficient way".

"Our troops' marching speed was about 6 km per hour, compared to the ordinary walking speed of 3-5 km per hour," the source told China Daily Wednesday.

"And that was on muddy mountain roads, carrying heavy bags of food, drugs, radios and quilts."

Wednesday morning, a helicopter carrying a nine-member taskforce equipped with radio and satellite phones landed in Wenchuan.

Telecommunication links between the county and the Chengdu Military Command were soon restored.

The PLA has devoted all its available facilities to the relief mission, including the Beidou satellite communication system, the Ilyushin Il-76 cargo aircraft, and remote-sensing aircraft for quake detection, the source said.

"The PLA has substantial expertise in relief operations given our experience in past disasters," the source said.

The PLA adjusted its original relief operation once the focus shifted from Wenchuan, the epicenter, to Beichuan county, where the situation turned out to be worse, he said.

"The headquarters is discussing the details," he said.

Soldiers and armed police yesterday carried out a blanket search for survivors and victims in Beichuan, he said.

"One thing is for sure, we will continue to send troops into affected areas," he said.