A 12-foot cross was scorched in the neatly trimmed suburban lawn of a high-ranking black school official who was implicated and then cleared in a grade-fixing scandal in Howard County.

Police announced yesterday that they were offering a $2,500 reward to anyone who could help them arrest the person or persons responsible for the large cross-shaped burn in the lawn of Kimberly Statham, chief academic officer of Howard County schools. Statham was one of two black school officials initially demoted in a dispute over whether she had used her influence to change her daughter's academic record.

Both were later restored to their posts, a decision that has stirred racial tension in the county in recent weeks.

Police were called to Statham's home on New Forest Court in Ellicott City on Wednesday by Statham's husband after he and the Stathams' two teenage children discovered the cross, which police say was possibly made with weed killer or some other chemical.

At a news conference yesterday afternoon, Police Chief G. Wayne Livesay denounced the incident, which he said was the first such hate crime to occur in Howard County in recent memory.

"We are taking this case very seriously," Livesay said. "We will do whatever it takes to solve this crime. We want to send a message that this type of behavior is not acceptable in Howard County."

Howard County NAACP President Jenkins Odoms Jr. joined Livesay in decrying the incident, which he said is part of a larger undercurrent of racism in the county stirred by "a few individuals who are filled with hate and bias."

Although Columbia prides itself on its diversity, "there are racists, hard core" beyond the planned community, he said at the news conference. About 75 percent of the county's population is white, and about 14 percent is black, according to the 2000 Census.

Police said that so far they have been unable to tie the cross incident to the controversy that has dogged Statham. But it follows some ugly episodes that began late last year, when an anonymous e-mail accused the two officials, Statham and Assistant Superintendent Roger L. Plunkett, of using their positions to alter a failing grade for Statham's daughter, a student at Centennial High School in Ellicott City. The e-mail also alleged that Statham had asked Plunkett to help change her daughter's transcript to show that the teenager had dropped a course rather than withdrawn from it.

After an investigation, the two were demoted in late February by John O'Rourke, shortly before he resigned as superintendent of schools. The two appealed, and in May, the county Board of Education reversed the demotions. The two were reinstated as administrators by Interim Superintendent Sydney L. Cousin, who has since been appointed permanently.

Cousin is on vacation, and his staff directed calls to police. Statham's office referred calls to her attorney, George Nilson, who said Statham is satisfied that police are working to find the perpetrator.

At a tumultuous meeting in early June, some black parents praised the decision to reinstate the two officials while some white parents spoke out angrily or left the meeting.

Afterward, the local NAACP chapter took out a two-page ad in the weekly Patuxent Publishing Co. newspapers, expressing dismay over the furor. In the "Open Letter," Odoms said he was reminded of "the lynch mobs of former years."