The Trump administration has begun building a border-wall section in Arizona near the Tohono O’odham Nation, despite the tribe’s objections. Federal authorities say the project is intended to curb drug smuggling, trafficking and illegal immigration through a remote desert corridor, while the tribe argues it will harm sacred land and amount to trespass.

The work forms part of a $46 billion border-security programme involving 30-foot steel bollards, vehicle barriers and surveillance technology. The 37,000-member tribe sued in June, warning of damage including to sacred mountain peaks, but a federal judge allowed the project to proceed because it is planned within the 60-foot-wide federally owned Roosevelt Reservation; tribal officials say contractors have since conducted soil sampling under CBP protection.