BOSTON (AP) — The eviction system, which saw a dramatic drop in cases before a federal moratorium expired over the weekend, rumbled back into action Monday, with activists girding for the first of what could be millions of tenants to be tossed onto the streets as the delta variant of the coronavirus surges.

Landlords tired of waiting for federal rental assistance were in court hoping to evict their tenants, while families from Ohio to Virginia turned up before judges hoping for a last-minute reprieve. In Detroit, at least 600 tenants with court orders against them were at immediate risk.

"It's...