A package that officials said contained two vials of a "homemade explosive substance" was discovered near the Arizona State Capitol in downtown Phoenix on Monday.
Philadelphia police investigated a report of a suspicious package at 30th Street Station on Sunday night.
Arizona has been a hot bed of extremist anger and threats against political and election officials. Those threats have been leveled against both Democratic and Republican leaders.
"As a repeated target of violence, it is reprehensible that Twitter allows C-list celebrities to encourage violence against me and my family," he tweeted.
Police were called to investigate a suspicious package at an Amazon Fulfillment Center in Gloucester County, New Jersey.
The NYPD has released a photo of a person of interest wanted for questioning in suspicious package scare at the Fulton Street subway station and near West 16th Street and 7th Avenue on Friday morning.