* Swiss voters back new surveillance law, early results show
* Law would expand spy agency tools to monitor militants
* Privacy advocates acknowledge defeat
By John Miller
ZURICH, Sept 25 (Reuters) - Swiss voters on Sunday were seen backing a law extending the national spy service's authority to monitor internet traffic, deploy drones and hack foreign computer systems, early returns published on Swiss state television showed.
The measure cleared Swiss Parliament a year ago, but privacy advocates and left-leaning political parties collected more than 50,000 signatures to put the measure on the ballot, customary in Switzerland's system of direct democracy.
The Swiss government had contended the nation's outdated intelligence laws had left Switzerland ill-equipped to tackle threats that have intensified as militants deploy new technology in a tight-knit global network.
The promise of more effective surveillance and subsequent security improvements resonated with voters worried that militant attacks such as those in neighbouring France and Germany could also hit Switzerland, political experts said.
"Swiss people understood the threat in concrete terms and acknowledged that an attack could come at any time," said Patrick Emmenegger, a professor of comparative political economy and public policy at Switzerland's University of St. Gallen. "Consequently, they were aware of the challenge -- and that newer, better tools were needed."
Opponents of the law, who raised the spectre of unprecedented mass surveillance, conceded defeat early Sunday afternoon but pledged to monitor how the law is applied in coming years.
"We are going to be keeping a careful watch," said Tamara Funiciello, president of the young people's wing of the Swiss Social Democratic party.
Across Europe, countries including France have expanded spy agency powers, following Islamist attacks that have shifted some governments' priorities from privacy to security.
A recent Polish surveillance law extends authorities' access to digital data and loosens the legal framework limiting surveillance by law enforcement.
While Switzerland has so far been unscathed by militant attacks, it has prosecuted several people it contends aided Islamic State.
Two other measures on Sunday's Swiss ballot, a so-called "Green Economy" initiative aiming to require businesses to use resources efficiently, and a measure that would have boosted retirement pension payments by 10 percent, were seen failing, according to early results. (Reporting by John Miller, editing bn Louise Heavens)
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