GUANGZHOU - As of 2 pm on Thursday, the death toll has risen to 48 after part of an expressway collapsed in south China's Guangdong province early Wednesday morning, according to a press conference held in Meizhou city.

The DNA of another three people has yet to be identified.

Thirty injured people are receiving hospital treatment, and none are in life-threatening condition, according to authorities of Meizhou.

The Ministry of Emergency Management has dispatched a team to the scene to guide rescue work, and has urged local efforts to accelerate search and rescue work, treat those who sustained injuries, minimize casualties, and determine the cause of the accident

The collapse happened around 2:10 am on the Meizhou-Dabu Expressway in Meizhou. The collapsed section measures 17.9 meters in length and covers an area of 184.3 square meters, officials said.

Aerial photos show one side of the expressway caved in, causing 23 vehicles to roll down a slope.

READ MORE: 24 dead after expressway collapse in China's Guangdong

The Ministry of Emergency Management has dispatched a team to the scene to guide rescue work, and has urged local efforts to accelerate search and rescue work, treat those who sustained injuries, minimize casualties, and determine the cause of the accident.

More than 500 personnel from local emergency response teams, mine rescue teams and the fire brigade have joined on-site rescue work.

The ministry has said that safety risks are relatively high on transportation, at tourist attractions and in densely populated areas during the May Day holiday, as the number of people traveling has increased.

The ministry will make further efforts to improve emergency plans, investigate potential risks, and strengthen safety precautions.

Meizhou city has arranged special personnel to provide comfort and tend to the families of the victims and those who remain missing. Following an investigation, it was determined that no foreigners were among the casualties, according to the press conference.

In order to ensure the strict prevention of secondary disasters, national and provincial geological experts have been sent to the scene to carry out an on-site investigation.

Seven observation points have been established to monitor the disaster area and its surrounding slopes around the clock, according to the press conference.

Data released at the press conference show that since the beginning of April, Meizhou has experienced multiple rounds of heavy rainfall. The average cumulative rainfall in the city was 621.7 millimeters last month, which was roughly 2.49 times more than the same period in normal years. It saw its highest level of precipitation during the month since meteorological records began, breaking the previous record of 437.3 millimeters set in 1980.

READ MORE: China renews yellow alert for rainstorm

Rainfall in Meizhou's Dabu county came in at 628.2 millimeters in April -- 2.75 times more than its annual average of 228.4 millimeters and its highest precipitation on record for the month of April, surpassing the previous record of 419.5 millimeters set in 1980.

The National Financial Regulatory Administration has guided insurance institutions to establish a special working group for the emergency handling of such events, integrating insurance resources and open green channels.

As of noon on Thursday, insurance institutions had prepaid insurance claims totaling 10.62 million yuan (about $1.49 million).