Alexandria Public Safety Director Charles T. Strobel sued six people in federal court yesterday, accusing them of conspiring to spread "a packet of false, scandalous, malicious and defamatory rumors" about him.

Strobel's action, which came two days after a special grand jury found a number of allegations against him were "baseless and unfounded," came in the form of a counterclaim to a civil rights suit filed against him and the City of Alexandria last month.

In addition to former Alexandria police detective Charles Cox and police officers Joseph Morrash and Morton Ford, Strobel's counterclaim names their lawyer Mary Craig, former Alexandria police officer Louis Pugh and Alexandria Port Packet managing editor Alicia Mundy as defendants. Strobel's action asks for $900,000 in damages from all six defendants and an additional $400,000 from Cox, Morrash, Ford and Craig.

Strobel charged that Craig, Morrash, Cox and Ford provided City Council member Donald C. Casey with "confidential police information for Casey's political gain, knowing that Casey had 'declared war' on Strobel and other officials of the City of Alexandria."

The special grand jury report, released Wednesday, said it found no evidence to back up allegations that Strobel prematurely halted a drug investigation last year, covered up an attempted homosexual act by a senior police officer, blocked an investigation of an Arlington murder or that he ran his department with a pattern of favoritism and cronyism.

Morrash, Cox, Ford and Craig brought the allegations about the drug investigation, cronyism and cover-up to city officials and then to the special grand jury. Mundy first disclosed the allegations about the drug investigation in The Port Packet, a community newspaper, on Dec. 20. Pugh said he testified to the special grand jury that in 1974 Strobel had stopped him from following up on a tip he had received about an Arlington murder.

Strobel's lawyer, David Fiske, said in a statement yesterday that it was "possible that certain other parties, including elected officials and certain local newspapers will be included as additional defendants in this action" later.

In its report the special grand jury excoriated unnamed City Council members for their "callous, politically motivated activities . . . in supporting the attempt to assassinate the character of . . . Strobel." Though no officials were named in the report, Mayor Charles E. Beatley and Casey have been Strobel's most vocal critics during the past two months.

"We have two comments," said Mundy. "The first is that we stand by our stories, and the second is that we look forward to the suit because it will give us the opportunity to bring forward witnesses and testimony to which the special grand jury did not give a hearing."

The other defendants could not be reached for comment.