Berlin: The threat of Islamist attacks in Germany is growing as numbers of people returning from militant camps on the Afghan-Pakistan border rise, a senior police official said.
Joerg Ziercke, head of the BKA Federal Crime Office, was also quoted on Sunday as saying that curbs on storing telecoms data were hurting efforts to track militant suspects.
More than 400 Islamists were living in Germany, some of whom had trained in camps, including a hard core with combat experience in Afghanistan, he told Tagespiegel newspaper.
Police had spotted a rise in German residents moving to and from the camps, he said in extracts of an interview to be published in Monday`s edition.
"Since the beginning of 2009, we have registered an increase in travel and attempted travel from members of violence-prone Islamist circles," he said.
"In Germany, we now classify 131 as potential instigators. These are people we assume could perpetrate politically motivated criminal acts of a considerable magnitude."
"We even have concrete proof 70 individuals completed paramilitary training in terror camps. Forty people have combat experience from battles in Afghanistan," he added.
Ziercke argued that a ruling in March by Germany`s highest court to limit archiving of telephone and Internet data was hindering investigations.
"That makes it considerably difficult when we have to clarify how perpetrators organise before a terrorist act, and determine who has communicated with whom," he said.
Saturday, Der Spiegel news weekly reported that a German Islamist held by US troops in Afghanistan and interrogated since July had revealed details of planned attacks on targets in Germany and Europe.
A spokesman for the German Foreign Ministry would not confirm details of the report, saying only that the government was trying to contact a citizen held by US forces. German media have said he came from the northern city of Hamburg.
Last month, German police shut down the Taiba Mosque in Hamburg, previously known as the Al-Quds Mosque, which was frequented by Mohammed Atta -- the leader of the group that carried out the attacks on the United States on September 11, 2001.
Police said the mosque had links with armed Islamist groups in Pakistan and Afghanistan.