The ruling Liberal Democratic Party was dealt a crushing blow Sunday after losing the Lower House by-elections in Okinawa and Osaka, viewed as a harbinger for the Upper House election just a few months away, Kyodo News projections showed.

The loss of both national races in the second wave of the unified elections marked a significant setback for Prime Minister Shinzo Abe, who doubles as head of the ruling party.

It is the first time the LDP has lost a national by-election since Abe's second term began in 2012, excluding the uncontested Lower House by-election in Kyoto Prefecture in 2016.