North Korea declared Tuesday that it would sever all communication and relations with Seoul as punishment for blaming the North for the sinking of a South Korean warship two months ago.

North Korea also announced it would expel all South Korean government officials working at a joint industrial park in the northern border town of Kaesong, the official Korean Central News Agency said in a dispatch monitored in Seoul late Tuesday.

Tensions were rising on the divided Korean peninsula in the wake of an investigation report blaming North Korea for a torpedo attack that sank the Cheonan warship on March 26, killing 46 South Korean sailors.

South Korea’s military restarted psychological warfare operations — including blaring radio broadcasts into the North and placing loudspeakers at the border to blast out propaganda — to punish the North for the provocation. The South is also slashing trade and denying permission to North Korean cargo ships to pass through South Korean waters.