A local man who made a fake bomb and threatened to blow up the Shenzhen branch of a school was arrested for extortion, prosecutors in Jiading District announced on Thursday.

The Jiading District People's Procuratorate says local police received a report from Shenzhen on September 23. According to the report, a man surnamed Zhang claimed to have planted a bomb at an unnamed training school in Shenzhen. He allegedly threatened to detonate the device unless the school met his demand for 1.5 million yuan (US$210,000).

Zhang, who is a manager of the Shanghai branch of the school in question, told prosecutors that at the end of 2017 he being paid less than his promised salary, 8,000 yuan, versus the 10,000 yuan he expected.

He reported the matter to the school several times but received no response, which made him believe that he was being treated unfairly, prosecutors say.

In August, Zhang allegedly came up with the idea of making a fake bomb to extort the school. He bought items like a timer, paper tubes and a battery online to make an object that resembled a bomb.

On September 23, Zhang allegedly sent pictures of the fake bomb to several executives of the school and told them it was put at its Shanghai branch. Here he also mentioned his demand for 1.5 million yuan, say prosecutors.

When he didn't receive the money that day, he was said to have contacted the school's Shenzhen branch with the same fake bomb claims.

The principle of the Shenzhen school was said to have paid Zhang 60,000 yuan to calm him down.

Zhang was apprehended by police two days later in Dongguan.