Former speaker is latest target of mailings sent to various Congress members in the lead-up to the midterm elections

California representative Nancy Pelosi’s office received “a suspicious letter” on Wednesday in what appears to be the latest incident of ill-intentioned mailings targeted at US Congress members before the midterm elections.

The offices of more than three dozen members of Congress across the political spectrum have received envelopes containing white powder in recent days. One lawmaker’s office said preliminary tests indicated the powder was not hazardous.

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Reporting from Jerusalem

The Israeli military has detained about 80 US, Israeli and British volunteers helping Palestinians harvest olives near Bethlehem, including the New York Democratic congressional nominee Brad Lander, several rabbis and Israel’s former deputy attorney general.