A young boy seems far from impressed as passengers wait to enter Beijing Railway Station on Tuesday. Even bigger crowds are expected over the next few days, as the Spring Festival travel rush gets into full swing. [ZOU HONG / CHINA DAILY]

Rail officials reported that unprecedented numbers of tickets are being returned by holiday passengers and suggested that more than 10 percent of the tickets bought could have been returned by the end of China's holiday travel rush this year.

Experts are suggesting the reason could be more flexible purchasing periods for tickets and lower charges to return a ticket.

According to a report on China Central Television, more than six million tickets have been sold daily during the rush so far, with around 700,000 of those being returned.

On average, 14,000 tickets have been returned daily at Beijing Railway Station since the rush started, said Chen Chao, the station's director of ticketing.

At Shanghai's three main stations, the rate is around 10,000 tickets per day, according to local news portal xinmin.cn.

Previous reports have suggested that on the three days after Jan 26, an average of 460,000 tickets were returned daily, against 250,000 in 2012.

Ji Jialun, a professor at Beijing Jiaotong University, told China News Service that longer purchase periods were allowing Chinese rail passengers much more flexibility, and lower charges being levied for returning tickets meant passengers were more willing to change their plans.

According to Ministry of Railways regulations, passengers can now buy railway tickets online or by telephone 20 days in advance for their trips, and 18 days in advance at ticketing windows.

One passenger named Ziliande Xiaoweiba said on Tuesday that she had found it easy to return her ticket after changing her plan. She was charged 5 percent of the full price of the ticket, against 20 percent charged before 2011.

However, it can be a time-consuming process if the ticket was bought at a railway station ticket window.

Ni Binyan, a vet from Jinan, capital of Shandong province, said there were queues at Jinan Railway Station on Tuesday of people returning tickets.

Ni waited almost an hour to return a ticket for a trip on Feb 11 from Jinan to Huaibei in Anhui province.

"When I bought a ticket for my trip on Feb 11, it was for a no-seat ticket. So when I found there were some tickets with seats, I decided to return this one," said Ni.

A telephone agent from 12306, the ticketing hotline of Beijing Railways Bureau, said that since Friday inquiries to return tickets had been rising, particularly for online bookings.

The bureau also said on its micro blog that by Saturday more than 700,000 railway tickets bought online had not been picked up by customers.

It said if customers wanted to return their purchased tickets, they should do so as soon as possible as those tickets could be sold again to other passengers.

Chen Chao, from Beijing Railway Station, reminded travelers that buying and returning ticket systems are connected, and that people can buy any returned railway tickets immediately.