A flurry of balloons from China have crossed the Taiwan Strait in the past week, passing over the self-governing island that Beijing claims as its own, according to Taiwan's defense ministry.

Why it matters: The crossings have come just days before Taiwan is set to hold its presidential and parliamentary elections and amid near-daily violations of Taiwan's airspace by Chinese air forces.

The balloons echo the floating vehicles that entered U.S. and Canadian airspace last year.

• The U.S. Department of Defense characterized the vehicles as spy balloons, raising concerns that Chinese intelligence were using them to collect information on military facilities.
• China denied close claims, instead saying they were civilian vessels used primarily for meteorological purposes.

What they're saying: The Ministry of National Defense of Taiwan said four Chinese balloons floating to the northeast crossed the Taiwan Strait on Tuesday.

• It said three of the vessels, which had altitudes between approximately 12 and 23 kilometers, eventually passed over the island before disappearing.
• The defense ministry said that same day, nine PLA aircraft from China's air force and four vessels belonging to China's navy were seen near Taiwan.
• At least two of the Chinese military aircraft crossed the median line of the Taiwan Strait and entered Taiwanese airspace, it added.

It was a similar story on Monday, with Taiwan discovering two Chinese balloons heading northeast and passing the Taiwan Strait before entering the island's airspace.

• One of the balloons disappeared after passing over the island, the defense ministry said.
• That same day, four Chinese military aircraft and three Chinese military naval vessels were detected near Taiwan, including one aircraft that entered the island's airspace.

The big picture: Taiwan's defense ministry has previously detected similar balloons in the past but described them then as weather monitoring vessels.

• However, this week, it declined to comment specifically on what it believed with the recently detected balloons were being used for, Reuters reports.
• Chinese President Xi Jinping in recent months has ratcheted up his rhetoric on Beijing's claims on Taiwan, most recently saying in his New Year's speech that China's "reunification" with the island is inevitable.
• Xi made similar claims during his meeting with President Biden in November, saying Beijing intends to reunify Taiwan and prefers taking the island peacefully and avoiding a military conflict, NBC News reported.
• Security experts have described China's deployment of ships and planes around Taiwan as "gray zone" tactics used to intimidate Taipei while simulating a blockade or other military operations against the island.

Go deeper: China's 2024 outlook will be shaped by decisions beyond its borders