Iran’s World Cup team arrived in Mexico wearing lapel pins highlighting the victims of a deadly missile strike on an elementary school at the start of the war.

The players wore gold-coloured pins with the number “168” on their jackets when getting off their plane on Sunday in Tijuana, Mexico. It referred to the people killed, most of them children, when a 28 February strike hit the school in Minab in southern Iran.

The strike on the school, which was close to a Revolutionary Guard base, was previously memorialised by the Iran team before a warm-up game in March in Antalya, Turkey. Players held up pink and purple school backpacks while their national anthem played.

Neither the United States nor Israel has accepted responsibility for the attack on the school, which has come under criticism from the United Nations and human rights groups. The US military said it is investigating.

Iran is preparing to play all three of its group-stage games in the US, which has delayed processing visas for players and has denied some to members of the delegation.