British counter-terrorism police say they are "deeply concerned" about the increasing number of girls and women travelling to Syria from the U.K., saying that many are unaware that they will likely never be able to return home.

Latest figures show that 56 women and girls were believed to have gone to Syria in 2015, compared to 43 in the previous year.

Police released the figures Tuesday along with a short film featuring three female Syrian refugees talking about life in their home country and urging British mothers to prevent their daughters traveling to the war zone.

Britain has seen several high-profile cases of young girls traveling to Syria to marry militants or support the Islamic State group.