In December 2016, the Center for the Study of Global Christianity (CSGC) at Gordon-Conwell Theological Seminary in Massachusetts, published a statement that "between 2005 and 2015 there were 900,000 Christian martyrs worldwide — an average of 90,000 per year, marking a Christian as persecuted every 8 minutes." However, the BBC has reported that others such as Open Doors and the International Society for Human Rights have disputed that number's accuracy. Gina Zurlo, the CSGC's assistant director, explained that two-thirds of the 90,000 died in tribal conflicts, and nearly half were victims of the civil war in the Democratic Republic of the Congo. Klaus Wetzel, an internationally recognized expert on religious persecution, explains that Gordon-Conwell defines Christian martyrdom in the widest possible sense, while Wetzel and Open doors and others such as The International Institute for Religious Freedom (IIRF) use a more restricted definition: 'those who are killed, "who would not have been killed", if they had not been Christians.' Open Doors documents that anti-Christian sentiment is presently based on direct evidence and makes conservative estimates based on indirect evidence. This approach dramatically lowers the numerical count. Open Doors says that, while numbers fluctuate every year, they estimate 11 Christians are currently dying for their faith somewhere in the world every day.