Facebook and Twitter have admitted they could do more to protect disabled people from online abuse, following criticism from the model and TV personality Katie Price, whose son Harvey has been victimised online.

The social media giants told MPs they could make the risks of abuse clearer to vulnerable people, and make the terms and conditions of using social media platforms easier for people with learning difficulties to understand.

Google, which runs the YouTube video platform, said it did not know whether it had consulted disabled people about making its terms and conditions clear to them. All three companies said they did not have any staff in the UK checking posts for abuse; their teams were based in Dublin.

The hearing in front of the Commons petitions committee came after Price launched a petition to make online bullying a criminal offence and to create a register of offenders.

“It’s got worse and worse,” she told the committee in February. “You name it [the form of abuse], Harvey’s got it.”

Price told the committee the complaints mechanism did not work properly because she did not receive a response when she flagged up abuse. 

Twitter’s head of public policy and government, Nick Pickles, said on Tuesday: “This is something we need to look at more.”

However, he said: “One of the things we struggle with a lot is that it is possible to be offensive without breaking our rules. One of the biggest challenges with offence is it is subjective … where something has happened on national television and then that is shared on social media it is very difficult for us to act on something that is made very public given that content is in the public domain.”

Karim Palant, Facebook’s UK public policy manager, said disabled people were considered a “protected group” under its protocols, and that the company would have 20,000 people worldwide checking posts by the end of this year. 

He said artificial intelligence software was able to pick up almost a third of the abuse, and Facebook took down 2.5m pieces of hate speech in the first quarter of this year.

The Labour MP Catherine McKinnell asked the companies what action they were taking on “mate crime”, saying “there are disabled people that have been befriended specifically with the intention of exploiting them”.

Palant said: “It’s a very challenging problem to solve using tools and technology. It looks like a genuine friendship. A lot of these are pre-existing relationships that may have started offline and are being carried on online.

“Realistically, we will make the reporting functions easier to access to people who are particularly vulnerable to some of these issues. Some of this is going to be about offline support and education … that we can provide.”