Police in east China's Jiangsu Province said Wednesday they had detained two men suspected of threatening to carry out new attacks following a string of school attacks last week.

Security guards contain an attacker with specially designed forks in a mocked attack in Dongming Middle School in Weifang, East China's Shandong province May 2, 2010.

A man surnamed Liu, 39, was detained on May 2, seven days after he sent a letter blackmailing the president of Chunxing Primary School in Wuxi City on April 26, local police said in a statement.

"If you don't want the tragedy in Nanping to repeat here in Wuxi...I'm so poor and I hope your school could help me out by putting 100,000 yuan (14,706 U.S. dollars) into my account... Otherwise, I'll have no other choice but to do it," the letter said, referring an attack in Nanping,Fujian Province, in which a man killed eight primary school children in March.

Liu confessed that he opened the bank account using someone's lost ID card.

Liu is under criminal detention awaiting further legal procedures.

Initial investigations showed that Liu had little school education, a meager income and gambled a lot.

Another man was placed in police custody for writing on-line: "find some kid to kill for fun." The man wrote the post in Jiangyin City, Wuxi, on May 1.

The 20-year-old surnamed Hu, who posted what he called "a joke" on the Internet just to attract people's attention, was given a three-day administrative detention from May 3 to 5.

The Wuxi municipal government has sent more than 1,000 police and 3,000 security guards to be on duty near local kindergartens, primary and junior high schools as of Wednesday.

Batons and pepper spray have been allocated to school security guards in Nanchang of the eastern Jiangxi Province.

Similar steps have also been taken in Shanghai, Changchun of the northeastern Jilin Province and Chengdu of the southwestern Sichuan Province following the recent attacks.