The companies and firms were the property of people related to selling dual-purpose materials to Pakistan. It is believed that the attacks were an attempt to avoid the development of nuclear weapons in Pakistan. The attacks left significant damage to buildings. They were also followed by a phone call to other companies suspected to have treaties with Pakistan, under threats of being the next target unless they quit the business.
In the meantime, a group named ‘Organization for the non-proliferation of nuclear weapons in South Asia’ demanded the responsibility for the attacks. Still, there were no further signs of it, and never again after the attacks.
Recently State Department documents were unclassified, which indicates the U.S. was not happy about Pakistan’s attempts to develop its own nukes. Still, the country did not want to alienate the Islamabad government. The U.S. government further tried to convince Bonn and Bern authorities to prevent the companies from continuing with the treaties of selling dual-purpose materials to Pakistan. The effort was in vain, and the people involved were further attacked.
According to the documents, Israel saw Pakistan's intentions as an existential threat and continued to take action on its prevention; otherwise, there is no concrete proof pointing to Israel, more than some circumstantial evidence that may implicate Mossad.
A businessman, who received threats during the attacks, told Swiss police that the Israeli Secret Service contacted him. He also reportedly told the investigators that a man named Mr. David, who worked in the Israeli embassy in Germany, had called him multiple times and even met him once in person to try and convince him to opt-out of business with Pakistan.