According to the FOCUS magazine, German authorities were not technically capable to crack the coded instructions, which were being sent to the both assailants up until they carried out the attacks.
"Once again we see how important the much-criticized NSA is for our safety," the source told the German outlet.
On July 18, an Afghan refugee attacked train passengers in Wuerzburg with an ax and wounded several people. Police subsequently shot the attacker dead.
On July 24, a Syrian national, whose asylum application had been turned down and who was to be deported to Bulgaria after living in Germany for a year, detonated a bomb in the Bavarian city of Ansbach, killing himself and injuring 15 bystanders.
The Daesh terror group, outlawed in Russia and many other countries worldwide, claimed responsibility for both attacks.