WASHINGTON, DC — China is believed to be responsible for an online hack targeting the congressional budget office that may have exposed its communications with US lawmakers.

An email from the senate sergeant-at-arms tells staffers that the incident is ongoing and they should avoid clicking on links sent from CBO accounts.

The office provides lawmakers with cost estimates on legislation.

China is blamed for other recent hacks targeting Washington as well, as its trade war with the US grew worse this year.