SAN FRANCISCO (KRON) — On Friday night, a swarm of aggressive bees attacked several East Bay residents. Two dogs were killed in the attack and several people suffered multiple stings.

The incident happened in Concord, but it’s been known for sometime that an African breed of honeybees, also known as killer bees, had made its way into the Bay Area.

UC San Diego researchers have been tracking the bees’ movement throughout California. Until now, the bees had only been detected in Mariposa County, just east of Merced.

Now, apparently because of warmer temperatures, they have been found in the East Bay, first spotted in a Lafayette subdivision reported in September 2015.

Below is a list from the United States Department of Agriculture that explains what you can do if you ever encounter an attack by bees.

What to do if Attacked by Africanized honey bees

Remember these important steps:

1. RUN away quickly. Do not stop to help others. However, small children and the disabled may need some assistance.

2. As you are running, pull your shirt up over your head to protect your face, but make sure it does not slow your progress. This will help keep the bees from targeting the sensitive areas around your head and eyes.

3. Continue to RUN. Do not stop running until you reach shelter, such as a vehicle or building. A few bees may follow you indoors. However, if you run to a well-lit area, the bees will tend to become confused and fly to windows.Do not jump into water! The bees will wait for you to come up for air. If you are trapped for some reason, cover up with blankets, sleeping bags, clothes, or whatever else is immediately available.

4. Do not swat at the bees or flail your arms. Bees are attracted to movement and crushed bees emit a smell that will attract more bees.

5. Once you have reached shelter or have outrun the bees, remove all stingers. When a honey bees stings, it leaves its stinger in the skin. This kills the honey bee so it can’t sting again, but it also means that venom continues to enter into the wound for a short time.

6. Do not pull stingers out with tweezers or your fingers. This will only squeeze more venom into the wound. Instead, scrape the stinger out sideways using your fingernail, the edge of a credit card, a dull knife blade or other straight-edged object.

7. If you see someone being attacked by bees, encourage them to run away or seek shelter. Do not attempt to rescue them yourself. Call 911 to report a serious stinging attack. The emergency response personnel in your area have probably been trained to handle bee attacks.

8. If you have been stung more than 15 times, or are feeling ill, or if you have any reason to believe you may be allergic to bee stings, seek medical attention immediately. The average person can safely tolerate 10 stings per pound of body weight. This means that although 500 stings can kill a child, the average adult could withstand more than 1100 stings.