However, witnesses said some of the black-clad gunmen who attacked a police station and government buildings in Baquba, 60 km (40 miles) northwest of Baghdad, proclaimed loyalty to Zarqawi and wore yellow headbands linking them to his group.
The clothes they wore was an indication to their affiliation
They were head bands that linked them 
( z1 indicate :ARG0 ( z2 clothes :ARG1-of ( z3 wear :ARG0 ( z4 they ) ) ) :ARG1 ( z5 affiliate :ARG1 z4 ) )