US intelligence chief warns Iran is stepping up efforts to target Americans

US Director of National Intelligence Jay Clayton has warned that Iran has "significantly increased" its efforts to target Americans. He issued the warning in Washington on Friday.

According to Clayton, Iran has stepped up efforts to target Americans not only in the Middle East but also in regions beyond it. The claim comes from the top US intelligence official.

Meanwhile, US President Donald Trump has signaled that military action against Iran could happen again. Trump said that if necessary, the United States could seize all of Iran's oil or bring the entire country under its control.

The intelligence chief's warning and President Trump's remarks are linked to the ongoing tension between the United States and Iran.