WASHINGTON — Amazon said Tuesday it is extending its ban on the use of its facial recognition tools for law enforcement, amid persistent concerns of bias in the technology.

The tech giant last June announced it was implementing a one-year moratorium on police use of its technology, saying the pause could give Congress time to enact safeguards against misuse of facial recognition.

The company confirmed Tuesday an extension of that ban “until further notice” without elaborating.

Last year’s move came amid widespread protests over police brutality and concerns that facial recognition technology is flawed, especially in analyzing features of African Americans.

Activists also say the technology tools may use algorithms which discriminate, intentionally or not, against Black people.

Activists have targeted Amazon Web Services cloud computing unit’s “Rekognition” facial recognition technology and Ring surveillance cameras used for home security. It was not clear the degree to which police have used the systems.

Amazon last year called for governments to put in place “stronger regulations to govern the ethical use of facial recognition technology.”

Its ban was followed by Microsoft and IBM, which made similar announcements.

Last week, a coalition of activist groups called for Amazon to permanently stop selling its Rekognition system and on Tuesday said the company should commit to scrapping the system.

“Facial recognition technology is too dangerous for it to be implemented at the whims of corporations like Amazon,” said Evan Greer of the activist group Fight for the Future, one of the groups in the coalition.