To the east of the Soviet Embassy, across the Yu He River, is the Japanese Embassy. Japanese guards on guard found that people from China frequently came and went here, and they always paid attention to it.

There is a French hospital in the west of the Soviet embassy. The staff of this hospital heard that there has been movement in the courtyard of the Russian military barracks next door, and some people are talking and arguing in the middle of the night.

The "movement" in the Soviet embassy attracted the attention of the French and Japanese embassies. I don't know whether it was intentional or not, but they told Wu Jin, the foreign minister at Zhang's headquarters at that time.

This Wu Jin studied in the French artillery engineering school and served as a counselor in the French embassy. He is a pro-French. He quickly reported the news that "there may be red activities in the Soviet embassy", which eventually led to the arrest of Comrade Li Dazhao.

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Before Li Dazhao was arrested

/kloc-in the summer of 0/926, Li Dazhao hid in the Russian military camp and was busy delivering information. At that time, the national army and the "red" Coalition forces were fighting fiercely at the south exit of Beijing. At the same time, the National Revolutionary Army swore allegiance to the northern expedition from Guangdong, and the war continued all the way, and the information was not smooth.

Li Dazhao, who stuck to Beijing, became the joint point connecting the North-South revolutionary struggle. A series of military intelligence and political intelligence gathered in the small courtyard of the Russian military barracks and then secretly transferred out. Write some unimportant words on the front of the information and write them in milk on the back. Only under the baking of fire will the handwriting appear.

At that time, it was already winter and spring. Yan Zhenshan, who was in charge of liaison work inside and outside the embassy beside Li Dazhao, went out to deliver letters one day and never came back. Zhang Quanyin carried the mail and picked up the newspaper, helping everyone cook and do odd jobs, but in a few days, Zhang Quanyin went shopping and disappeared.

And you don't know, four spooks sent by the capital police department have long been recruited as handymen and sneaked into the Russian military camp, staring at the every move of the China people in the military camp.

A few days later, Li Dazhao and many other revolutionaries hiding in the barracks were unfortunately arrested.

Baidu Encyclopedia-Li Dazhao