Officials at both Herndon and South Lakes high schools discovered vandalism at their athletic facilities within the past week, just days before the 2013-14 school year was to begin on Tuesday. In the search for the culprits, Fairfax County police are investigating whether the incidents are related.

Last Thursday, school officials discovered obscene language spraypainted on a storage shed and the football field at Herndon. On Saturday, similar profane graffiti was found on two new turf fields at South Lakes, according to Fairfax County Public Schools spokesman John Torre.

Vulgar and sexually explicit derivations of the South Lakes nickname, the Seahawks, was found on both the stadium and practice fields as well as on the track and walkways within the stadium. Torre said that the school officials are in the process of powerwashing and painting to repair the damage, and security has been increased at both schools.

“The investigation is a police matter at this point,” Torre said. “We are working with the Fairfax County police to try to hold accountable those who are responsible for this.”

Both schools will play their football season openers at home on Friday, with South Lakes hosting No. 14 Westfield and Herndon welcoming Mount Vernon.

The new football field and community field at South Lakes were installed this summer at the cost of approximately $1.4 million, with most of the funds raised by the community.

“It’s very disappointing since we had just installed the new turf field, and now before the first day of school, it’s been vandalized,” said Mike Jennings, who has been active in the South Lakes athletic booster club with his wife and whose two sons graduated from the Reston high school in the past four years. “I’m not sure what the options are in preventing something like this, but hopefully they can track down whoever did this.”

Torre said that an email will be sent Tuesday by the principals of both schools to inform parents of the incidents and encourage anyone with information about the vandalism to report it to the police.

South Lakes Athletic Director Linda Jones declined comment and directed questions to the FCPS office.