NEW YORK, June 24: Germany has been at heightened alert against terrorist attacks since its military involvement in Afghanistan, says a report in the New York Times, quoting German officials.

The danger level, they warned, was comparable to the months before the 9/11 attacks in the United States.

Three Germans, believed to be radical militants, were arrested in Pakistan in recent days, according to the German Federal Criminal Police. Officials here suspect them of travelling to the Pakistan-Afghanistan border region to enter terrorist training camps, the newspaper said.

“This tells us that German interests are in danger of being attacked, for example, by suicide bombers,” a spokesman for the Interior Ministry, Christian Sachs, told the Times in a telephone interview.

He said the authorities did not have concrete evidence of a terrorist plot within Germany. But the police have tightened border security and are scrutinising people travelling to and from Pakistan and Afghanistan.

German soldiers and civilians in Afghanistan face the most immediate threat, officials said, citing an attack last weekend on a convoy outside Kabul that included vehicles from the German Embassy.

There were no injuries, but a vehicle was destroyed, a government spokesman said.