By Angela Harrison
BBC News education reporter
The school district says the laptops had a "security device"
Parents in the US have accused a school of spying on children by remotely activating webcams on laptops.
A couple from Pennsylvania have filed a lawsuit against a school district which gave laptops to its high school pupils.
They say their son was told off by teachers for "engaging in improper behaviour in his home" and that the evidence was an image from his webcam.
Lower Merion School District says it has now deactivated a tracking device installed on the laptops.
It says the security feature was only used to track lost, stolen and missing laptops.
But it was deactivated on Thursday and would not be re-instated without informing students and families, the district said.
'Stages of undress'
The Lower Merion School District gave the laptops to all 1,800 students at its two high schools with the aim of giving them access to school resources around the clock, according to its website.
Michael and Holly Robbins are suing the district on behalf of their child and all the children in the district issued with the laptops.
They allege the school district invaded their privacy and are guilty of "wiretapping" by putting children under covert surveillance.
In their lawsuit, they claim the webcams were activated remotely and images were taken which could have included anything going on in a room where the laptop was placed.
The legal papers say: "As the laptops were routinely used by students and family members at home, it is believed that many of the images captured and intercepted may consist of images of minors and their parents or friends in compromising or embarrassing positions, including in various stages of dress or undress".
On Thursday, the Lower Merion School District posted a letter to parents on its website saying it had always "gone to great lengths" to protect the privacy of its students.
In it, the Schools Superintendent Christopher McGinley gives details of the security feature, which he said was activated only if a laptop was reported lost, stolen or missing.
"The security feature's capabilities were limited to taking a still image of the operator and the operator's screen," he wrote.
"This feature was only used for the narrow purpose of locating a lost, stolen or missing laptop. The District never activated the security feature for any other purpose or in any other manner whatsoever."
However, the district had carried out a preliminary review of security procedures and had disabled the security-tracking program, he added.
The district would now conduct a thorough review of the existing policies for student laptop use and look at any other "technology areas in which the intersection of privacy and security may come into play".
"We regret if this situation has caused any concern or inconvenience among our students and families, " he said.