The FBI are searching for a 22-year-old man sought in connection with a wave of pipe-bombs found in rural mailboxes in the US.
The announcement came shortly after a pipe bomb similar to 17 others found in five states was discovered in a rural mailbox in Amarillo, Texas with a letter attached.
That bomb appeared to be from the same source as others found, the FBI said.
Most of the earlier bombs were accompanied by anti-government notes that warned "more 'attention getters' are on the way."
"It's another pipe bomb. It looks similar to the others," said FBI agent Mr Larry Holmquist in Omaha. "Upon our initial inspection, it appears it would be from the same source."
There have been no arrests and no injuries reported since six people were hurt.
Authorities said anti-government notes found with most of the earlier devices were nearly identical and profiling experts have said whoever wrote them is probably an older American man.
PA