BEIJING (Reuters) - A ride-sharing passenger in the eastern Chinese city of Wenzhou was raped and killed by a driver for China’s largest ride-hailing firm, local police said on Saturday, the latest violent crime to fuel safety concerns about the service.

FILE PHOTO: A man is seen in front of a Didi sign before a promotional event of its Hitch service for the Spring festival travel rush, in Beijing, China January 24, 2018. REUTERS/Stringer/File Photo

Didi Chuxing, the biggest ride-sharing firm globally by number of trips, was “immensely saddened by the tragedy,” it said in a statement.

“We are deeply sorry. We fell short of your expectations. We can’t and we won’t shirk from our responsibilities,” it said.

Following the incident, Zhejiang province, where Wenzhou is located, ordered Didi to suspend its carpooling service there while the company addressed safety issues, the official Xinhua news agency reported.

Didi has been stepping up safety measures including for its carpooling service, Didi Hitch, after the murder of a flight attendant in May sparked wider community outrage.

The steps include limiting Didi Hitch drivers to picking up passengers of the same sex during early morning and late evening hours.

Police in Yueqing city, which is part of Wenzhou, said on their official microblog that the 20-year-old woman, surnamed Zhao, got into a Didi carpool vehicle at 1 p.m. on Friday, and sent a message to a friend at around 2 p.m. seeking help before losing contact.

Police said they found the suspect, a 27-year-old driver called Zhong, at about 4 a.m. on Saturday. They said Zhong confessed to raping and killing the passenger, and that the victim’s body had been recovered and an investigation was continuing.

Didi said the driver had passed background checks and had logged in with his authentic ID and had been confirmed by facial recognition on the day. However, the driver had altered the car’s licence plate before the trip, the company said.

A day earlier, a passenger had complained to Didi that the same driver had repeatedly requested that she sit in the front seat, drove to a remote area, and followed her “for a distance” after she got out of the car, Didi said. It said the customer service representative who took the complaint had not followed up with an investigation within two hours, as the firm promises.

Didi Chuxing - which has been valued at $50 billion and counts SoftBank Group Corp 9984.T as a major investor - is aggressively expanding overseas, targeting new markets in Mexico, Brazil and Australia, going head-to-head with Uber. In 2016, Didi acquired Uber's China business.

“The fact that Didi has a driver safety and security issue is a real problem for Didi ... and an opportunity for new service providers who can better serve the mobility demand,” said Bill Russo, CEO of Automobility Limited, a Shanghai-based consultancy.

The latest case was also trending on the Twitter-like Weibo platform, with seven related topics in the top 50 on Saturday afternoon.