Hamas has announced the appointment of Yahya Sinwar as its new leader following the assassination of Ismail Haniyeh in Tehran on July 31. Sinwar, previously the head of the group's operations inside the Gaza Strip, takes the helm at a critical time for the organization.

The announcement came on Tuesday, cementing Sinwar's position as the new head of Hamas's political bureau. Sinwar, a key figure within Hamas, is known for his strategic leadership and hardline stance. He was instrumental in the planning of the October 7 attacks on southern Israel, which resulted in significant casualties and heightened tensions in the region.

Sinwar's history with Hamas is extensive. He was close to the group's founder, Sheikh Ahmed Yassin, and played a pivotal role in establishing Hamas's internal security bodies. In the late 1980s, Sinwar was sentenced by Israel to four life terms for his involvement in leading Hamas's first internal security apparatus, Majd, which targeted and killed Palestinians suspected of collaborating with Israel. He served 23 years before being released in 2011 as part of a prisoner exchange for Israeli soldier Gilad Shalit.

Since his release, Sinwar has risen through the ranks of Hamas, becoming a prominent leader within the group. In 2017, he was appointed as the head of Hamas's operations in Gaza. His leadership has been marked by a focus on military strategy and internal security.

The assassination of Haniyeh in Tehran has added to the complexities facing Hamas. Haniyeh was in Iran to attend the swearing-in ceremony of the new Iranian president, Masoud Pezeshkian. He was reportedly killed by a "projectile" while staying at a residence for war veterans, an incident that Hamas attributes to an Israeli strike.