Indian authorities have arrested a computer scientist for refusing to divulge the source of an electronic voting machine that he and a team of researchers used to expose holes in the country's election system.

The Hyderabad home of Hari Prasad, managing director of Netindia LTD, was raided on Saturday morning at 5:30 by authorities who questioned him for two and a half hours before taking him into custody, a colleague of his said here. Police then transported him to Mumbai, which is about 14 hours away.

The arrest follows research released in April that disclosed several vulnerabilities in India's electronic voting machines, which authorities have claimed are fully tamper-proof and even perfect. The flaws were discovered on a machine that an anonymous source donated to the research team in February, after elections officials refused to make one available.

“The police did not state a specific charge at the time of the arrest, but it appears to be a politically motivated attempt to uncover our anonymous source,” J. Alex Halderman, one of the members of the team that exposed the vulnerabilities, wrote on Sunday. “The arresting officers told Hari that they were under 'pressure [from] the top,' and that he would be left alone if he would reveal the source's identity.”

In 2009, officials from the Election Commission of India publicly challenged Prasad to prove the machines were flawed but then refused to give him access to one of the devices. The team – which besides Prasad and Halderman also included Rop Gonggrijp – was able to continue with the help of the anonymous source.

“We have every reason to believe that the source had lawful access to the machine and made it available for scientific study as a matter of conscience, out of concern over potential security problems,” Halderman wrote.

In April, the team released this paper (PDF), which identified several hardware-based attacks that insiders with physical access to the machines could use to falsify elections. The paper didn't cover software-based vulnerabilities because the researchers weren't able to extract the code without destroying the device.

Concern has been growing in India about the reliability of e-voting. In April, 13 political parties representing about half of India's electorate wrote to elections officials to express their concerns, according to Indiaevm.com. Earlier this month, more than two dozen scientists and researchers wrote India's chief election commissioner to warn of vulnerabilities in the country's electronic voting machines. A PDF of their letter is here. ®