England were victims of a theft of their training equipment before their arrival in Kansas City on Saturday.
The Football Association is trying to ascertain what was stolen, with balls and boots among the items feared to have been taken, after vehicles transferring equipment to their Swope Soccer Village base in Kansas City were broken into.
Thomas Tuchel and his squad will arrive in Kansas City on Saturday afternoon and the equipment was due to be in place beforehand.
Police officers, who are in touch with the FA, were on site on Friday night dealing with the matter.
It is understood two arrests have been made in connection with the episode.
A spokesman for Kansas Police said: "We are investigating a possible theft of equipment from a team vehicle that arrived in Kansas City with items missing this evening. The investigation is ongoing."
The theft could potentially disrupt some of Tuchel's preparations for their World Cup opener against Croatia on Wednesday (21:00 BST).
The England players will undertake their first full training day on Sunday.