The Israeli Defense Force (IDF) and Hamas, the militant Islamist group in control of the Gaza Strip, don’t officially communicate with each other. But on Twitter Tuesday, the enemy groups shared an extremely rare interaction.

The Israeli army’s chief foreign media spokesman, Peter Lerner, tweeted a defense of the arrest in the West Bank of a Palestinian involved in a 2012 bus bombing, which ended with the suspect dead. Surprisingly, the official Twitter account of Hamas’ military wing, Alqassam Brigades, tweeted back. Alqassam told the lieutenant colonel it would continue its “holy struggle” and resistance until the liberation of Palestine. The tweet used the hashtags “#Palestine” and “#Zionists.”

Lerner favorited the Alqassam tweet and wrote back, “Israel is here to stay.” He hashtagged his tweet “#TerrorDoesntPay.” (Hamas has been classified as a terrorist organization by Israel, the United States, Canada, Japan, and the European Union.)

@AlqassamBrigade our mission is one of safeguarding human life, all human life. #TerrorDoesntPay — Peter Lerner (@LTCPeterLerner) October 22, 2013

This not the first time the IDF and Hamas have communicated on social media. Last year, the IDF used Twitter to warn Hamas that officials on their side should go into hiding or risk being targeted by IDF military action. But before Tuesday’s exchange, their communication had always been one-way. Though Hamas regularly tweets at the IDF, Israeli officials told the Wall Street Journal they never planned to respond to those tweets.

So, why a reply this time?

Lerner told the Journal that tweeting directly with Hamas allowed followers to see arguments from both sides. “It’s the wonders of social media. You can connect easily,’’ he said. “They reached out and I responded.”

H/T Wall Street Journal / Photo via IDF/Flickr