Why do they get lost?
According to the Ministry of Civil Affairs, as of December 2015, China has 222 million senior citizens, accounting for 16.1 percent of the total population. In the next two decades, 10 million more people will join their ranks every year. By the end of 2050, the elderly will make up one-third of the population.
Liu said elderly people are not been abducted on a huge scale, and neither are thousands of them fleeing home. Most of them go missing because they have a form of dementia or are otherwise disabled.
"These old people can't clearly remember their identity and home address. It's hard for the police to help them find their families. And those with dementia or similar related conditions go missing frequently and this is irreversible. If modern medical tools can't cure them, this will get more and more serious," he said.
In China, more than 11 million people have either dementia, similar conditions or are otherwise disabled, said Liu.
Besides these conditions, the problems with traditional elderly care are another issue contributing to this problem.
Due to the belief that pious children should take care of their elderly parents at home, and the financial difficulties facing many families, a large number of seniors unable to look after themselves do not live in formal care facilities.
Many of these elderly people spend a lot of time alone as their children are working, often in cities with which they are unfamiliar.
Liu Shenghua, an official at Liyuan police station in Beijing, said that according to the reports about missing elderly people they have received in recent years, there are three major reasons behind this phenomenon.
The first is due to relocation and the difficulties elderly people have with getting acquainted with a new neighborhood. The second is that they often know little about the city as a whole. The third is they have dementia or other memory problems.
According to statistics from the Beijing health bureau, there are 150,000 to 200,000 elderly people with dementia or similar conditions in the capital. China has the largest number of Alzheimer's patients in the world.
Take me home
Statistics from a police station in Ningbo, East China's Zhejiang Province revealed that in 2015 they received 157 reports concerning missing senior citizens.
Statistics released by police in Hubei Province showed that between January and October 2015, they received 17,951 missing person reports. They received 21,456 such reports in 2014. Most of these reports were about elderly people.
Toutiao says that as of July 14, it has successfully helped find 100 people through 1,443 messages they pushed to their app users. Among them, 54 were aged above 60. Some 22 had Alzheimer's and 24 had mental disorders.
A substantial chunk of the missing seniors get hurt or even die before they are found. "This number is very high," Liu told the Southern Weekly.
Cao Lizhen, 62 year old, lost a leg after going missing in Shenzhen, Guangdong Province. Cao's son said the doctor said that her mother's injury was caused by a big blow, like a car accident.
To combat this serious problem, now governments and NGOs are taking on this challenge.
Half month after Lu Qianyu's incident, Lanxi's civil affairs bureau handed out free GPS devices to elderly people with Alzheimer's or other disabilities in 20 communities.
The government has also launched an online platform where people can register and once they report a person as missing, the platform will send special signals to elderly persons's GPS device. The margin of error is less than five meters.
The Beijing government also gives out free bracelets which serve as real-time monitors to track elderly people's location.
Zenghua said that if an elderly person goes missing, they will estimate the distance they may have walked in the time they've been missing. "A conservative estimate is they can walk five kilometers per hour," he said.
Through estimating where the missing senior might be, Toutiao sends targeted alerts to their users in these areas.
This tactic has proved effective. In July, they found an old man six minutes after getting a report that he was missing. Now the Ministry of Civil Affairs is working with Toutiao on this.
Liu Hongcheng said that Toutiao offers an innovative way to track people down and greatly increase the efficiency of search efforts.
"But the aging society is a social phenomenon. There are still lots of things that need to be done by the police, social assistance organizations and families," he said.
