BERLIN (AP) — Germany's auction of frequencies for a super-fast 5G network has ended after nearly three months, raising more money for the government than was originally expected: 6.55 billion euros ($7.4 billion).

The Federal Network Agency on Wednesday announced the end of the auction, which opened on March 19. The auction involved bids from existing network operators Deutsche Telekom, Vodafone and Telefonica, as well as newcomer Drillisch.

It was expected to raise 3 to 5 billion euros, money the government wants to invest in digitalization — such as better IT equipment for schools.

Network security wasn't directly an issue in the auction but has simmered in recent months. German authorities put together security requirements stipulating that system suppliers had to be "trustworthy."

They don't specifically mention Chinese technology giant Huawei, which the U.S. alleges poses an espionage threat.