More pipe bombs targeting members of the Democratic Party and a critic of U.S. President Donald Trump were discovered Thursday. Investigators found three more pipe bombs: one sent to actor Robert De Niro and the others to former Vice President Joe Biden. They said the devices were similar to the pipe bombs sent this week to former President Barack Obama, Hillary Clinton and CNN television. The package found at CNN was addressed to John Brennan, a fierce critic of Trump and a former director of intelligence under Obama. Others were sent to businessman George Soros, a long-time Democratic Party supporter, and Representative Maxine Waters, a Democrat from California. One package mailed to former Attorney General Eric Holder, who served under Obama, was returned to the office of Representative Debbie Wasserman Schultz. She was a former chair of the Democratic Party. Actor Robert De Niro has long been a vocal critic of President Trump. At the Tony Awards in June, the actor used an obscenity to insult the president.