Philadelphia firms with operations in Germany are closely watching the security situation there following Monday night's terrorist attack on a Christmas market in Berlin, but they see no need to change business practices or step up precautionary measures.

Germany is a large market for American firms, and the United States is a fertile place for German companies to do business. Americans with business in Germany said that, for now, there was little sign the attack would affect employees, disrupt supply chains, or cool U.S.-based businesses' ardor for investing in the booming German market.

"From an employee standpoint, from a customer standpoint, I don't see it" affecting business, said William Strecker, president and CEO of Kingsbury Inc., a Philadelphia-based manufacturer of specialty ball bearings with a plant in Goettingen, Germany.

Goettingen, a mid-size university town in the north central part of the country far from Berlin, is an unlikely site for a terror attack. Strecker said he would become concerned if the attacks increased in number and moved closer to Goettingen.

Twelve people were killed and more than 50 injured, many seriously, Monday night when a tractor trailer ploughed through an outdoor Christmas market outside the Kaiser Wilhelm Memorial Church in the heart of Berlin.

Police are seeking a 24-year-old Tunisian man who came to Germany last year amid the influx of refugees from the Middle East and Afghanistan. The suspect, Anis Amri, had been under surveillance for having ties to radical Islamists. He was to be deported, but had managed to elude authorities.

Even in Berlin, a sense of calm has prevailed, said Stefan Peikert, a partner with AHP International, which advises German firms seeking to establish a foothold in Pennsylvania and clients in the U.S. seeking to do business in Germany.

"We were prepared that one day something would happen and that it would happen in Berlin, probably," said Peikert, who is based in Berlin. "But you look at what happened in Berlin after the attack, and it is totally different from what happened in France, no panic, the city has decided to carry on," to the extent that the Christmas markets have reopened.

Peikert says potential political disruptions, which could add to business uncertainty, have been muted. Many commentators have suggested the Berlin attack will fuel the rise of the nationalist Alternative for Germany party, undercutting the government of Chancellor Angela Merkel and her Christian Democratic Union party. Yet Peikert notes the AFD, while winning several important state parliament elections earlier this year, has been leveling off in the polls.

An AFD demonstration in Berlin against Merkel after the attack drew only a few score supporters, far fewer than the hundreds of journalists and counter demonstrators who also showed up.

Jack Rosenbloom, a mergers and acquisition lawyer in Horsham who heads the AHP office for the U.S., said business conditions now are so favorable that he doubted the attacks would diminish American businesses' interest in investing in Germany.

"It's a horribly tragic situation [the attack on the Christmas market], but the economic and business ties between the two countries are so strong … that we don't see any long-term affect," Rosenbloom said.

Ralf Wiedemann, the honorary consul of Germany in Philadelphia and an immigration lawyer at Green and Spiegel LLP, said one attack in Berlin, horrific though it was, would not be enough to derail American investment plans in Germany that have been in the works a while.

If anything, the attack likely will reinforce the idea that among European nations, Germany is not immune to the plague of terrorism that has hit France, Belgium, the United Kingdom and Spain.