Four people were arrested by Abu Dhabi authorities on charges of "tribal instigation and libel'' through posts on social networking site Twitter, the state-run WAM news agency reported.
The three Emirati men and a Palestinian woman will remain in custody for 14 days pending investigation.
The arrests stem from insults being traded in a "heated discussion'' between the Palestinian woman and the three Emirati men via the website last month.
"Some people do not understand the grave consequences of their conducts on social networking sites or over the Internet in general,'' the state news agency reported, citing an unidentified official from the office of Abu Dhabi Attorney General.
"There are no problems facing authorities in combating such conduct,'' the official was quoted as saying. "Ignorance of laws is not at all a waiver of legal responsibility,'' he added.
Last month, police in neighbouring emirate Dubai announced that authorities would begin round-the-clock monitoring of social media websites.
Posts on websites such as Twitter and Facebook are now subject to checks by anti-electronic crime teams in Dubai and other emirates as part of a bid to crackdown on abuse and defamation, Major Salem Obaid Salmeen, deputy director of anti-electronic crimes at Dubai Police’s CID said.
Quoted first on the programme Rouh Al Qanoon on Radio Noor Dubai, Salmeen said monitoring of these websites was not a violation of people’s personal freedoms, given that the information is already public.
He said electronic patrol teams would track “all topics and materials written and presented” on the websites, and any “violation of the law” would be considered abuse, and be punishable.
He added that Dubai police is equipped with the latest technologies in the field, which would allow its experts to find the source of the abuse. This would be held on a government server for 18 months, he said.