- Erwin Sperisen was head of Guatemala's national police from 2004 to 2007
- He is accused of involvement in extrajudicial killings, the Swiss judicial authority says
- Sperisen is also wanted by Guatemala, an anti-impunity NGO says
- He holds dual Swiss-Guatemalan nationality so cannot be extradited
Police in Switzerland arrested Guatemala's former national police chief over allegations he was involved in extrajudicial killings while in office, the judicial authority in Geneva said.
Erwin Sperisen, 42, who was detained Friday afternoon, holds dual Swiss and Guatemalan nationality and lives in Geneva, the judicial authority said in a statement.
"Details provided by the Guatemalan authorities at the end of 2011 and recent developments in the case raise important suspicions about the suspect's involvement in various extrajudicial executions committed while he was director of Guatemala's national police from July 2004 to March 2007," it said.
Claims against Sperisen had also been filed by various associations in 2007 and 2008, it said.
A coalition of non-governmental organizations has been working on the case against Sperisen, said Trial, a Swiss non-governmental organization that aims to combat impunity.
An international arrest warrant was issued by Guatemala for Sperisen in 2010, Trial said in a statement.
Trial and rights group Amnesty International had since urged the Swiss authorities to act, it said.
Sperisen cannot be extradited to Guatemala because he holds Swiss nationality, the judicial authority said.
Trial said the coalition of NGOs involved "welcomes the steps taken by the Swiss prosecuting authorities."
The arrest "represents a major advance in the case" and demonstrates "the credibility of the charges" brought against Sperisen, it said.