An 18-year-old high school student cast Wednesday the first early vote in Japan's House of Representatives election, which was open to those aged 18 and 19 for the first time.

Natsuki Nakagawa was at the head of the queue outside a polling station in Mino, Osaka Prefecture when it opened at 6:30 a.m., the earliest to do so in the country.

A third-year student at a prefectural high school, Nakagawa said a mock exam will keep her away from the polls when general voting takes place on Oct. 22.

"Since I'm going to (cast an early vote), I thought I'd try to be the first to vote," she said. "I thought all the forms would be a hassle, but it was easy."

Nakagawa said she keeps tabs on politics through the news and parliamentary broadcasts and discusses the issues with her father.

She said she chose her party and candidate based on their foreign policies, taking into account North Korea's nuclear and ballistic missile development programs and other international issues.

Next in line to vote was another 18-year-old -- third-year private high school student Sho Hattori.

"When I thought about how my one vote could change Japan, my heart was racing and I felt the weight (of what I was doing)," he said.

Hattori said he made his choice after comparing parties' policies online, particularly on the consumption tax increase planned for 2019 and on nuclear power.

"Before they raise the tax, I'd like them to make clear where (the revenue) is going to be used," he said.

While polling stations generally opened from 8:30 a.m. to 8 p.m. for early voting in the general election in 2014, an amendment to the electoral law last year enabled local authorities to open them up to two hours earlier and close up to two hours later.

The same amendment also lowered the voting age to 18 from 20, taking effect just before the July 2016 House of Councillors election.

The city of Mino decided last year to open the polling place near its main train station two hours early, aiming to boost turnout by making voting more convenient.