A new database allows people to track some of the hundreds of British citizens who left the country to join jihadist groups in Iraq and Syria, particularly ISIS and Al Qaeda’s Nusra Front.

The database, compiled over the past three months by the BBC, includes extensive information on each person, including pictures, aliases, and biographical information.

Based on open source information, independent research, and help from the disapproving families of the jihadists, the list currently includes about eighty people and is divided into three categories: those who are currently in Syria or Iraq, those who were killed while fighting for jihadist groups, and those who were convicted for activities related to Syria or Iraq. Viewers can further filter the lists by gender, age, hometown, convictions, and terrorist group.

Reviewing dozens of cases together reveals several significant patterns. The majority are in their late teens or 20s and male, though about a quarter are women and there are fighters who were in their 30s and 40s before dying. Most significantly, rather than being spread throughout the country, British jihadists tend to arise in groups. This suggests either the presence of local cells or people convincing their friends to join the fighting together with them.

The project is still incomplete. Security officials say they believe there to be at least 600 Britains who have joined foreign jihadist groups and about 50 who have been killed while fighting for them.

The full database can be seen here.