* Regional court orders arrest for leaving YouTube videos up
* Second judge in 2 weeks ordering arrest over elections law
SAO PAULO, Sept 25 (Reuters) - A regional elections court in Brazil has ordered the arrest of the head of Google's operations in the country after the company failed to take down YouTube videos attacking a local mayoral candidate.
The ruling, which Google is appealing, marks the second time in two weeks that Brazilian judges have ordered the apprehension of executives at the search engine giant for not cooperating with local election laws.
The legal challenges highlight broader questions about Google's responsibility for content that third parties upload to its websites, such as an anti-Islam video that sparked a wave of protests and violence in the Muslim world.
A spokesman for the regional elections court in Mato Grosso do Sul said on Tuesday that a judge had ordered the arrest of Fabio José Silva Coelho, Google's top executive in Brazil, unless the videos attacking a local mayoral candidate were removed.
"Google is appealing the decision that ordered the removal of the video on YouTube because, as a platform, Google is not responsible for the content posted to its site," the company said through a spokesman in Brazil.
Earlier this month an electoral court in the state of Paraiba ordered the arrest of another senior Google executive, Edmundo Luiz Pinto Balthazar, after the company refused to take down a YouTube video mocking a mayoral candidate there.
Days later another judge overturned the ruling.
At the time, the company also defended in a statement its users' rights of expression.
"Google believes that voters have a right to use the Internet to freely express their opinions about candidates for political office, as a form of full exercise of democracy, especially during electoral campaigns," the company wrote.